Energy storage device and energy storage system

Abstract

An energy storage device (10) and an energy storage system (100) are provided. The energy storage devices (10) are used for being electrically connected with the energy storage converters (20), the energy storage converters (20) can be used for being matched with the M energy storage devices (10), the rated output power of the energy storage converters (20) is P, the energy of the energy storage devices (10) is Q, the duration of discharging the energy storage devices (10) from a full charge state to a full discharge state is A, and P / (M * Q / A) is larger than or equal to 0.7 and smaller than or equal to 0.99. P / (M * Q / A) is smaller than or equal to 0.99, so that the power of all the energy storage devices (10) matched with the energy storage converter (20) has enough allowance compared with the power of the energy storage converter (20), the capacity of the energy storage devices (10) does not need to be supplemented within a long time, and long-term reliability of the energy storage devices (10) is achieved. P / (M * Q / A) is greater than or equal to 0.7, so that the margin of the power of the energy storage device (10) compared with the power of the energy storage converter (20) is not excessive, the power waste is reduced, and the economical efficiency of the energy storage device (10) is improved. In this way, the power matching between the energy storage device (10) and the energy storage converter (20) is improved.

Description

Energy storage devices and energy storage systems

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to the international application entitled “Energy Storage Device and Energy Storage System” (PCT / CN2023 / 101942) filed on June 21, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present application relates to the field of energy storage technology, and in particular to an energy storage device and an energy storage system. Background Art

[0004] Energy storage devices are devices that store and transfer electrical energy. They can be used in power systems to store excess energy during off-peak periods to supplement peak demand. Therefore, energy storage devices can both store excess power from a power generation system and deliver power to the grid during periods of low power generation.

[0005] Energy storage devices typically consist of a housing and multiple battery cells mounted within it. These cells are connected in series, parallel, or hybrid to store electrical energy. Energy storage devices typically require connection to an energy storage inverter to charge and discharge the device. Currently, the power compatibility between energy storage devices and energy storage inverters is poor.

[0006] Summary of the Invention

[0007] The embodiments of the present application provide an energy storage device and an energy storage system, which can effectively improve the power matching between the energy storage device and the energy storage converter.

[0008] In a first aspect, an embodiment of the present application provides an energy storage device for electrically connecting to an energy storage converter. The energy storage converter can be used in conjunction with M energy storage devices, where M is a positive integer, the rated output power of the energy storage converter is P, in W, the energy of the energy storage device is Q, in Wh, and the time it takes for the energy storage device to discharge from a fully charged state to a fully discharged state is A, in h, satisfying the following: 0.7≤P / (M*Q / A)≤0.99.

[0009] In the above technical solution, if P / (M*Q / A) ≤ 0.99, the power of all energy storage devices used with the energy storage converter has sufficient margin compared to the power of the energy storage converter, eliminating the need for additional capacity additions to the energy storage devices over a long period of time and ensuring the long-term reliability of the energy storage device. If P / (M*Q / A) ≥ 0.7, the power margin between the energy storage device and the power of the energy storage converter is moderate, reducing power waste and improving the economic efficiency of the energy storage device. This improves the power matching between the energy storage device and the energy storage converter from the perspective of long-term reliability and economic efficiency.

[0010] In some embodiments, 0.75≤P / (M*Q / A)≤0.95. This balances the long-term reliability and economy of the energy storage device, thereby keeping the cost of the energy storage device at a low level and increasing the capacity replenishment cycle of the energy storage device.

[0011] In some embodiments, 0.85≤P / (M*Q / A)≤0.93.

[0012] In some embodiments, the energy storage device includes a housing and at least one battery. The housing includes a battery compartment, which contains at least one battery. The battery includes at least one battery cell. The capacity of the battery cell is C, measured in Ah. The platform voltage of the battery cell is U0, measured in V. The total number of battery cells in the battery compartment is N, where Q = N*C*U0. This ensures that all battery cells in the battery compartment have equal capacity, allowing the use of battery cells of the same specifications. This improves the assembly efficiency of the energy storage device and reduces the possibility of space waste due to different specifications of battery cells in the battery compartment.

[0013] In some embodiments, the battery compartment accommodates N1 batteries, the N1 batteries are formed by X1 first battery groups connected in parallel, and each first battery group is formed by Y1 batteries connected in series; or, the N1 batteries are formed by Y1 second battery groups connected in series, and each second battery group is formed by X1 batteries connected in parallel, satisfying: N1≥1, X1≥1, Y1≥1, N1=X1*Y1; the battery includes N2 battery cells, the N2 battery cells are formed by X2 first battery cell groups connected in parallel, and each first battery cell group is formed by Y2 battery cells connected in series; or, the N2 battery cells are formed by Y2 second battery cell groups connected in series, and each second battery cell group is formed by X2 battery cells connected in parallel, satisfying: N2≥1, X2≥1, Y2≥1, N2=X2*Y2, N=N1*N2. For the N1 batteries in the battery compartment, Y1 batteries can be connected in series to form a first battery group, and then X1 first battery groups can be connected in parallel; or X1 batteries can be connected in parallel to form a second battery group, and then Y1 second battery groups can be connected in series. For the N2 battery cells in the battery, Y2 battery cells can be connected in series to form a first battery group, and then X2 first battery groups can be connected in parallel; or X2 battery cells can be connected in parallel to form a second battery group, and then Y2 second battery groups can be connected in series. The number of batteries in series Y1 in the battery compartment and the number of battery cells in series Y2 can be set as needed to adjust the voltage of the energy storage device to a reasonable range.

[0014] In some embodiments, when the energy storage device is charging, the maximum operating voltage on the DC side of the energy storage converter is U1, and the minimum operating voltage on the DC side of the energy storage converter is U2, satisfying the following: U2 < U0 * Y1 * Y2 < U1. This allows the voltage of the energy storage converter to match the voltage of the energy storage converter, enabling both external devices to charge the energy storage device through the energy storage converter and the energy storage device to supply power to external devices through the energy storage converter.

[0015] In some embodiments, the positive electrode material of the battery cell includes a lithium-containing phosphate, 2.8V ≤ U0 ≤ 3.6V, and 250 ≤ Y1*Y2 ≤ 468. Thus, when the positive electrode material of the battery cell includes a lithium-containing phosphate, the voltage of the energy storage converter can be controlled within a reasonable range. This not only prevents the voltage of the energy storage device from being too low, allowing the energy storage device to be compatible with an energy storage converter with a higher operating voltage, but also prevents the voltage of the energy storage device from being too high, thereby reducing the operating voltage requirement for the energy storage converter and lowering production costs.

[0016] In some embodiments, the positive electrode material of the battery cell includes lithium iron phosphate, 3.1V≤U0≤3.3V, 400≤Y1*Y2≤424. Thus, when the positive electrode material of the battery cell includes lithium iron phosphate, the voltage of the energy storage converter can be controlled within a reasonable range.

[0017] In some embodiments, 3.5*10 6 W≤P≤7.5*10 6 W, M = A, 1 ≤ X1 * X2 ≤ 18. The positive electrode material of the battery cell includes lithium phosphate, 3.5 * 10 6 W≤P≤7.5*10 6 W, and when M=A, X1*X2 can be set in the range of 1 to 18 to control the capacity of the battery cell within a reasonable range.

[0018] In some embodiments, X1=1.

[0019] In some embodiments, X2=1, 2000Ah≤C≤11000Ah. When the positive electrode material of the battery cell includes lithium-containing phosphate, and the parallel number X1 of the batteries in the battery compartment and the parallel number X2 of the battery cells are both 1, setting the capacity of the battery cell within the range of 2000Ah to 11000Ah can meet both the power matching requirements and the voltage requirements of the energy storage device.

[0020] In some embodiments, 2500Ah≤C≤6000Ah.

[0021] In some embodiments, X2=2, 1000Ah≤C≤5500Ah. When the positive electrode material of the battery cell includes lithium-containing phosphate, the parallel number X1 of the batteries in the battery compartment is 1, and the parallel number X2 of the battery cells is 2, setting the capacity of the battery cell within the range of 1000Ah to 5500Ah can meet both the power matching requirements and the voltage requirements of the energy storage device.

[0022] In some embodiments, 2000 Ah ≤ C ≤ 4000 Ah.

[0023] In some embodiments, 2≤X1≤6. In this way, the number X1 of batteries connected in parallel in the battery compartment is controlled within a reasonable range, which not only prevents the capacity of the battery cells from being too large, thus reducing the difficulty and cost of manufacturing the battery cells, but also prevents the number X1 of batteries connected in parallel in the battery compartment from being too large, thereby improving the space utilization of the battery compartment.

[0024] In some embodiments, X1=4, X2=1, and 500Ah≤C≤2600Ah. When the positive electrode material of the battery cell includes a lithium-containing phosphate, and X1=4, X2=1, setting the capacity of the battery cell within the range of 500Ah to 2600Ah can meet both the power matching requirements and the voltage requirements of the energy storage device.

[0025] In some embodiments, 800Ah≤C≤1500Ah.

[0026] In some embodiments, X1=4, X2=2, and 250Ah≤C≤1300Ah. When the positive electrode material of the battery cell includes a lithium-containing phosphate, and X1=4, X2=2, setting the capacity of the battery cell within the range of 800Ah to 1500Ah can meet both the power matching requirements and the voltage requirements of the energy storage device.

[0027] In some embodiments, 350Ah≤C≤1000Ah.

[0028] In some embodiments, 500Ah≤C≤700Ah.

[0029] In some embodiments, X1 first battery packs are arranged along the length of the housing. When the positive electrode material of the battery cells includes a lithium-containing phosphate and 2 ≤ X1 ≤ 6, arranging the X1 first battery packs connected in parallel within the battery compartment along the length of the housing can fully utilize the space in the battery compartment along the length of the housing, resulting in a reasonable layout and improved space utilization within the battery compartment.

[0030] In some embodiments, the battery compartment includes multiple sub-compartments arranged along the length of the housing, with each sub-compartment housing a first battery pack. Dividing the battery compartment into multiple sub-compartments, each of which can accommodate a first battery pack, allows the first battery pack to be more regularly accommodated within the battery compartment, making it easier to install the batteries in the first battery pack.

[0031] In some embodiments, the positive electrode material of the battery cell includes a lithium transition metal oxide, 2.8V≤U0≤4.35V, and 210≤Y1*Y2≤530. Thus, when the positive electrode material of the battery cell includes a lithium transition metal oxide, the voltage of the energy storage converter can be controlled within a reasonable range. This not only prevents the voltage of the energy storage device from being too low, allowing the energy storage device to be compatible with an energy storage converter with a higher operating voltage, but also prevents the voltage of the energy storage device from being too high, thereby reducing the operating voltage requirement for the energy storage converter and lowering production costs.

[0032] In some embodiments, 3.5*10 6 W≤P≤7.5*10 6 W, M = A, 1 ≤ X1 * X2 ≤ 18. The positive electrode material of the battery cell includes lithium transition metal oxide, 3.5 * 10 6 W≤P≤7.5*10 6 W, and when M=A, X1*X2 can be set in the range of 1 to 18 to control the capacity of the battery cell within a reasonable range.

[0033] In some embodiments, X1=1.

[0034] In some embodiments, X2=1, 1500Ah≤C≤13400Ah. When the positive electrode material of the battery cell includes a lithium transition metal oxide, and the parallel number X1 of the batteries in the battery compartment and the parallel number X2 of the battery cells are both 1, setting the capacity of the battery cell within the range of 1500Ah to 13400Ah can meet both the power matching requirements and the voltage requirements of the energy storage device.

[0035] In some embodiments, 3000Ah≤C≤7000Ah.

[0036] In some embodiments, X2=2, 750Ah≤C≤6670Ah. When the positive electrode material of the battery cell includes a lithium transition metal oxide, the number of parallel batteries in the battery compartment X1 is 1, and the number of parallel battery cells X2 is 2, setting the capacity of the battery cell within the range of 750Ah to 6670Ah can meet both the power matching requirements and the voltage requirements of the energy storage device.

[0037] In some embodiments, 1800Ah≤C≤4000Ah.

[0038] In some embodiments, 2≤X1≤6. In this way, the number X1 of batteries connected in parallel in the battery compartment is controlled within a reasonable range, which not only prevents the capacity of the battery cells from being too large, thus reducing the difficulty and cost of manufacturing the battery cells, but also prevents the number X1 of batteries connected in parallel in the battery compartment from being too large, thereby improving the space utilization of the battery compartment.

[0039] In some embodiments, X1=4, X2=1, and 375Ah≤C≤3300Ah. When the positive electrode material of the battery cell includes a lithium transition metal oxide, and X1=4, X2=1, setting the capacity of the battery cell within the range of 375Ah to 3300Ah can meet both the power matching requirements and the voltage requirements of the energy storage device.

[0040] In some embodiments, 700Ah≤C≤1600Ah.

[0041] In some embodiments, X1=4, X2=2, and 200Ah≤C≤1600Ah. When the positive electrode material of the battery cell includes a lithium transition metal oxide, and X1=4, X2=2, setting the capacity of the battery cell within the range of 200Ah to 1600Ah can meet both the power matching requirements and the voltage requirements of the energy storage device.

[0042] In some embodiments, 340Ah≤C≤1050Ah.

[0043] In some embodiments, 490Ah≤C≤720Ah.

[0044] In some embodiments, X1 first battery packs are arranged along the length of the casing. When the positive electrode material of the battery cells comprises a lithium transition metal oxide, and 2 ≤ X1 ≤ 6, arranging the X1 first battery packs connected in parallel within the battery compartment along the length of the casing can fully utilize the space in the battery compartment along the length of the casing, resulting in a reasonable layout and improved space utilization within the battery compartment.

[0045] In some embodiments, the battery compartment includes multiple sub-compartments arranged along the length of the housing, with each sub-compartment housing a first battery pack. Dividing the battery compartment into multiple sub-compartments, each of which can accommodate a first battery pack, allows the first battery pack to be more regularly accommodated within the battery compartment, making it easier to install the batteries in the first battery pack.

[0046] In some embodiments, the battery cells are sodium-ion battery cells, 1.5V≤U0≤4V, and 230≤Y1*Y2≤1000. Thus, when the battery cells are sodium-ion battery cells, the voltage of the energy storage converter can be controlled within a reasonable range, which not only prevents the voltage of the energy storage device from being too low, allowing the energy storage device to be compatible with the energy storage converter with a higher operating voltage, but also prevents the voltage of the energy storage device from being too high, thereby reducing the operating voltage requirements of the energy storage converter and lowering production costs.

[0047] In some embodiments, 3.5*10 6 W≤P≤7.5*10 6 W, M = A, 1 ≤ X1 * X2 ≤ 18. When the battery cell is a sodium ion battery cell, 3.5 * 10 6 W≤P≤7.5*10 6 W, and when M=A, X1*X2 can be set in the range of 1 to 18 to control the capacity of the battery cell within a reasonable range.

[0048] In some embodiments, X1=1.

[0049] In some embodiments, X2=1, 1200Ah≤C≤18000Ah. When the battery cells are sodium-ion battery cells, and the parallel number X1 of the batteries in the battery compartment and the parallel number X2 of the battery cells are both 1, the capacity of the battery cells is set within the range of 1200Ah to 18000Ah, which can meet both the power matching requirements and the voltage requirements of the energy storage device.

[0050] In some embodiments, 2000 Ah ≤ C ≤ 10000 Ah.

[0051] In some embodiments, X2=2, 600Ah≤C≤9000Ah. When the battery cells are sodium-ion battery cells, the parallel number X1 of the batteries in the battery compartment is 1, and the parallel number X2 of the battery cells is 2, the capacity of the battery cells is set within the range of 600Ah to 9000Ah, which can meet both the power matching requirements and the voltage requirements of the energy storage device.

[0052] In some embodiments, 1600Ah≤C≤4000Ah.

[0053] In some embodiments, 2≤X1≤6. In this way, the number X1 of batteries connected in parallel in the battery compartment is controlled within a reasonable range, which not only prevents the capacity of the battery cells from being too large, thus reducing the difficulty and cost of manufacturing the battery cells, but also prevents the number X1 of batteries connected in parallel in the battery compartment from being too large, thereby improving the space utilization of the battery compartment.

[0054] In some embodiments, X1=4, X2=1, and 300Ah≤C≤4000Ah. When the battery cell is a sodium-ion battery cell, and X1=4, X2=1, the capacity of the battery cell is set within the range of 300Ah to 4000Ah, which can meet both the power matching requirements and the voltage requirements of the energy storage device.

[0055] In some embodiments, 700Ah≤C≤1500Ah.

[0056] In some embodiments, X1=4, X2=2, and 150Ah≤C≤1500Ah. When the battery cell is a sodium-ion battery cell, and X1=4, X2=2, the capacity of the battery cell is set within the range of 150Ah to 1500Ah, which can meet both the power matching requirements and the voltage requirements of the energy storage device.

[0057] In some embodiments, 350Ah≤C≤1200Ah.

[0058] In some embodiments, 400Ah≤C≤650Ah.

[0059] In some embodiments, X1 first battery packs are arranged along the length of the case. When the battery cells are sodium-ion battery cells and 2 ≤ X1 ≤ 6, arranging the X1 first battery packs connected in parallel within the battery compartment along the length of the case can fully utilize the space in the battery compartment along the length of the case, resulting in a reasonable layout and improved space utilization within the battery compartment.

[0060] In some embodiments, the battery compartment includes multiple sub-compartments arranged along the length of the housing, with each sub-compartment housing a first battery pack. Dividing the battery compartment into multiple sub-compartments, each of which can accommodate a first battery pack, allows the first battery pack to be more regularly accommodated within the battery compartment, making it easier to install the batteries in the first battery pack.

[0061] In some embodiments, the battery compartment accommodates only one first battery pack along the height of the housing, and Y1 batteries in each first battery pack are arranged along the height of the housing, where 2≤Y1≤10. Arranging all batteries in the first battery pack along the height of the housing facilitates the series connection of all batteries in the first battery pack. Setting Y1 between 2 and 10 prevents Y1 from being too large. The number of batteries arranged along the height of the housing within the battery compartment is limited, which helps improve space utilization within the battery compartment.

[0062] In some embodiments, a battery cell includes a shell and at least one electrode assembly, and the electrode assembly is accommodated in the shell; the shell is in the shape of a right parallelepiped, the size of the shell in the first direction is W1, the size of the shell in the second direction is T1, and the size of the shell in the third direction is K1, one of the first direction, the second direction and the third direction is parallel to the length direction of the shell, another is parallel to the width direction of the shell, and the third is parallel to the height direction of the shell; the shell includes a first wall and a second wall arranged opposite to each other along the first direction, a third wall and a fourth wall arranged opposite to each other along the second direction, and a fifth wall and a sixth wall arranged opposite to each other along the third direction, the sum of the thicknesses of the first wall and the second wall is a, the sum of the thicknesses of the third wall and the fourth wall is b, and the sum of the thicknesses of the fifth wall and the sixth wall is c, satisfying: (W1-a)*(T1-b)*(K1-c) / (W1*T1*K1)≥90%. In such a battery cell, the ratio of the volume of the internal space of the battery cell shell to the volume of the shell is above 90%, so that the internal space of the shell accounts for a large proportion, and the space of the shell that can be used to accommodate the electrode assembly is increased. Under the same chemical system, the volume energy density of the battery cell can be improved.

[0063] In some embodiments, (W1-a) / W1≥97%, (T1-b) / T1≥96.5%, and (K1-c) / K1≥96.5%. This can increase the proportion of the internal space of the housing in three dimensions, further increasing the volume energy density of the battery cell.

[0064] In some embodiments, the housing includes a shell and an end cap, wherein the shell has an opening and the end cap is engaged with the opening; the shell includes a first wall, a second wall, a third wall, a fourth wall, and a fifth wall that are integrally formed, and the end cap serves as the sixth wall. When assembling the battery, the electrode terminals can be first mounted on the end caps, the electrode assembly can then be accommodated within the shell, and the end caps can then be engaged with the opening of the shell. This can reduce the difficulty of installing the electrode assembly within the shell and the difficulty of installing the electrode terminals on the shell.

[0065] In some embodiments, the battery cell further includes a first insulating member and a second insulating member. The first insulating member is disposed between the fifth wall and the electrode assembly and abuts the fifth wall; the second insulating member is disposed between the sixth wall and the electrode assembly and abuts the sixth wall. The maximum dimension of the first insulating member in the third direction is e1, and the maximum dimension of the second insulating member in the third direction is e2, satisfying the following conditions: (W1-a-1.6mm)*(T1-b-1.6mm)*(K1-c-e1-e2) / (W1*T1*K1)≥88%, 0.3mm≤e1≤1.2mm, and 2mm≤e2≤10mm. This increases the space within the housing for the electrode assembly, allowing for the accommodation of a larger electrode assembly, thereby further improving the volumetric energy density of the battery cell.

[0066] In some embodiments, the battery cell further includes a first insulating member and a second insulating member. The first insulating member is disposed between the fifth wall and the electrode assembly and abuts the fifth wall; the second insulating member is disposed between the sixth wall and the electrode assembly and abuts the sixth wall. The maximum dimension of the first insulating member in the third direction is e1, and the maximum dimension of the second insulating member in the third direction is e2, satisfying the following conditions: (W1-a-4mm)*(T1-b-4mm)*(K1-c-e1-e2) / (W1*T1*K1)≥85%, 0.3mm≤e1≤1.2mm, and 2mm≤e2≤10mm. This increases the space within the housing for the electrode assembly, allowing for the accommodation of a larger electrode assembly, thereby further improving the volumetric energy density of the battery cell.

[0067] In some embodiments, W1 ≥ T1, the first direction is parallel to the length of the housing, the second direction is parallel to the width of the housing, and the third direction is parallel to the height of the housing. If only one end of the housing is provided with an end cap and W1 ≥ T1, the end cap and the fifth wall of the housing are arranged relative to each other along the height of the housing, the first and second walls of the housing are arranged relative to each other along the length of the housing, and the third and fourth walls of the housing are arranged relative to each other along the width of the housing. This is beneficial for increasing the volume share of all battery cells within the battery compartment.

[0068] In some embodiments, the housing includes a shell and two end covers, the shell has two openings arranged opposite to each other along a third direction, and the two end covers respectively cover the two openings; the shell includes an integrally formed first wall, a second wall, a third wall and a fourth wall, and the two end covers are respectively the fifth wall and the sixth wall.

[0069] In some embodiments, the battery cell further includes a third insulating member and a fourth insulating member. The third insulating member is disposed between the fifth wall and the electrode assembly and abuts the fifth wall. The fourth insulating member is disposed between the sixth wall and the electrode assembly and abuts the sixth wall. The maximum dimension of the third insulating member in the third direction is e3, and the maximum dimension of the fourth insulating member in the third direction is e4, satisfying the following conditions: (W1-a-1.6mm)*(T1-b-1.6mm)*(K1-c-e3-e4) / (W1*T1*K1)≥88%, 2mm≤e3≤10mm, and 2mm≤e4≤10mm. This increases the space within the housing for the electrode assembly, allowing for the accommodation of a larger electrode assembly, thereby further improving the volumetric energy density of the battery cell.

[0070] In some embodiments, the battery cell further includes a third insulating member and a fourth insulating member. The third insulating member is disposed between the fifth wall and the electrode assembly and abuts the fifth wall. The fourth insulating member is disposed between the sixth wall and the electrode assembly and abuts the sixth wall. The maximum dimension of the third insulating member in the third direction is e3, and the maximum dimension of the fourth insulating member in the third direction is e4, satisfying the following conditions: (W1-a-4mm)*(T1-b-4mm)*(K1-c-e3-e4) / (W1*T1*K1)≥85%, 2mm≤e3≤10mm, and 2mm≤e4≤10mm. This increases the space within the housing for the electrode assembly, allowing for the accommodation of a larger electrode assembly, thereby further improving the volumetric energy density of the battery cell.

[0071] In some embodiments, W1 ≥ T1, the first direction is parallel to the height of the housing, the second direction is parallel to the width of the housing, and the third direction is parallel to the length of the housing. When end caps are provided at both ends of the housing and W1 ≥ T1, the two end caps are arranged along the length of the housing, the first and second walls of the housing are arranged along the height of the housing, and the third and fourth walls of the housing are arranged opposite each other along the width of the housing. This helps to increase the volume share of all battery cells within the battery compartment.

[0072] In some embodiments, 3000 cm 3 ≤W1*T1*K1≤40000cm 3 W1*T1*K1≥3000cm 3 , so that the wall thickness of the shell is not too small while the ratio of the volume of the internal space of the shell to the volume of the shell is above 90%, thereby meeting the structural strength requirements of the shell; W1*T1*K1≤40000cm 3 , the capacity and current of the battery cell can be controlled within an appropriate range, reducing the risk of damage to overcurrent components in the circuit.

[0073] In some embodiments, 3200 cm 3 ≤W1*T1*K1≤32000cm 3 It takes into account both the structural strength of the shell and the heat generation requirements of the battery cells, further improving the structural strength of the shell and reducing the risk of damage to overcurrent components in the circuit.

[0074] In some embodiments, 3720 cm 3 ≤W1*T1*K1≤12500cm 3 .

[0075] In some embodiments, 4000 cm 3 ≤W1*T1*K1≤6000cm 3 .

[0076] In some embodiments, the positive electrode material of the battery cell includes a lithium-containing phosphate and satisfies the following conditions: C ≥ 350 Ah, and C / ((W1-a)*(T1-b)*(K1-c)) ≥ 118 Ah / L. When the positive electrode material of the battery cell includes a lithium-containing phosphate and C ≥ 350 Ah, setting C / ((W1-a)*(T1-b)*(K1-c)) to above 118 Ah / L can increase the volume ratio of the internal space of the battery cell housing, facilitating achieving a ratio of the volume of the internal space of the battery cell housing to the volume of the housing of 90% or greater.

[0077] In some embodiments, the positive electrode material of the battery cell includes a lithium transition metal oxide and satisfies the following conditions: C ≥ 650 Ah, and C / ((W1-a)*(T1-b)*(K1-c)) ≥ 190 Ah / L. When the positive electrode material of the battery cell includes a lithium transition metal oxide and C ≥ 650 Ah, setting C / ((W1-a)*(T1-b)*(K1-c)) to above 190 Ah / L can increase the volume ratio of the internal space of the battery cell housing, facilitating achieving a ratio of the volume of the internal space of the battery cell housing to the volume of the housing of 90% or greater.

[0078] In some embodiments, the battery cell is a sodium-ion battery cell that satisfies the following conditions: C ≥ 260 Ah, and C / ((W1-a)*(T1-b)*(K1-c)) ≥ 87 Ah / L. When the battery cell is a sodium-ion battery cell and C ≥ 260 Ah, setting C / ((W1-a)*(T1-b)*(K1-c)) to above 87 Ah / L can increase the volume ratio of the internal space of the battery cell housing, which is conducive to achieving a ratio of the volume of the internal space of the battery cell housing to the volume of the housing of 90% or more.

[0079] In a second aspect, an embodiment of the present application provides an energy storage system, comprising an energy storage converter and M energy storage devices provided by any one embodiment of the first aspect, wherein the energy storage device is electrically connected to the energy storage converter.

[0080] In some embodiments, M=2, A=2; or, M=4, A=4; or, M=8, A=8. BRIEF DESCRIPTION OF THE DRAWINGS

[0081] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0082] FIG1 is a schematic block diagram of an energy storage system provided in some embodiments of the present application;

[0083] FIG2 is an axonometric diagram of an energy storage device provided in some embodiments of the present application;

[0084] FIG3 is a schematic structural diagram of an energy storage device provided in some embodiments of the present application;

[0085] FIG4 is a schematic structural diagram of the box shown in FIG3 ;

[0086] FIG5 is an AA cross-sectional view of the box shown in FIG4 ;

[0087] FIG6 is an exploded view of the battery shown in FIG3 ;

[0088] FIG7 is an exploded view of the battery cell shown in FIG6 ;

[0089] FIG8 is a diagram illustrating the arrangement of batteries within the battery compartment shown in FIG3 ;

[0090] FIG9 is a diagram illustrating the arrangement of batteries in a battery compartment according to some other embodiments of the present application;

[0091] FIG10 is a schematic structural diagram of a battery provided in some embodiments of the present application;

[0092] FIG11 is a schematic structural diagram of batteries provided in other embodiments of the present application;

[0093] FIG12 is a schematic structural diagram of an energy storage device provided in other embodiments of the present application;

[0094] FIG13 is a schematic structural diagram of the box shown in FIG12;

[0095] FIG14 is a BB cross-sectional view of the energy storage device shown in FIG12 ;

[0096] FIG15 is an axonometric view of a battery cell provided in some embodiments of the present application;

[0097] FIG16 is an exploded view of the battery cell shown in FIG15 ;

[0098] FIG17 is a cross-sectional exploded view of the battery cell shown in FIG15 taken along the UW plane;

[0099] FIG18 is a cross-sectional exploded view of the battery cell shown in FIG15 taken along the VW plane;

[0100] FIG19 is an axonometric view of a battery cell provided in some other embodiments of the present application;

[0101] FIG20 is an exploded view of the battery cell shown in FIG19 ;

[0102] FIG21 is a cross-sectional exploded view of the battery cell shown in FIG19 taken along the UW plane;

[0103] FIG22 is a cross-sectional exploded view of the battery cell shown in FIG19 taken along the VW plane.

[0104] Icons: 1-box; 11-battery compartment; 111-sub-compartment; 112-partition; 113-support; 12-thermal management compartment; 13-main control compartment; 14-electrical compartment; 2-battery; 2a-first battery group; 2b-second battery group; 21-battery cell; 21a-first battery cell group; 21b-second battery cell group; 211-housing; 2111-shell; 2112-end cover; 2113-first wall; 2114-second wall; 2115-third wall; 2116-fourth wall; 2117-third Fifth wall; 2118-sixth wall; 212-electrode terminal; 213-electrode assembly; 2131-ear; 214-first insulating member; 215-second insulating member; 216-third insulating member; 217-fourth insulating member; 22-battery box; 221-first part; 222-second part; 10-energy storage device; 20-energy storage converter; 100-energy storage system; U-first direction; V-second direction; W-third direction; X-length direction of the box; Y-width direction of the box; Z-height direction of the box. DETAILED DESCRIPTION

[0105] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0106] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0107] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments.

[0108] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "attached" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0109] The term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0110] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of the various components in the embodiments of this application, as well as the overall thickness, length, width, and other dimensions of the integrated device shown in the drawings are merely illustrative and should not constitute any limitation on this application.

[0111] The term "plurality" used in this application refers to two or more (including two).

[0112] In the embodiment of the present application, the battery cell may be a secondary battery. A secondary battery refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0113] Battery cells include but are not limited to lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-hydrogen batteries, nickel-cadmium batteries, lead-acid batteries, etc.

[0114] A battery cell typically includes an electrode assembly. This assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process, active ions (such as lithium ions) move back and forth between the positive and negative electrodes. A separator, placed between the positive and negative electrodes, reduces the risk of short circuits while allowing active ions to pass through.

[0115] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0116] As an example, the positive electrode current collector has two surfaces facing each other in its thickness direction, and the positive electrode active material is provided on either or both of the two facing surfaces of the positive electrode current collector.

[0117] As an example, the positive electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, aluminum with a silver-plated surface, stainless steel with a silver-plated surface, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel or titanium, etc. may be used. The composite current collector may include a polymer material base layer and a metal layer. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0118] As an example, the positive electrode active material may include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides, and modified compounds thereof. However, this application is not limited to these materials; other conventional materials that can be used as positive electrode active materials for batteries may also be used. These positive electrode active materials may be used singly or in combination of two or more.

[0119] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0120] As an example, the negative electrode current collector can be a metal foil, a metal foam, or a composite current collector. For example, as the metal foil, aluminum or stainless steel with a silver surface treatment, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium can be used. The metal foam can be nickel foam, copper foam, aluminum foam, alloy foam, or carbon foam. The composite current collector can include a polymer material base layer and a metal layer. The composite current collector can be formed by forming a metal material (copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

[0121] As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

[0122] As an example, the negative electrode current collector has two surfaces facing each other in its thickness direction, and the negative electrode active material is provided on either or both of the two facing surfaces of the negative electrode current collector.

[0123] As an example, the negative electrode active material may adopt the negative electrode active material for battery cells that is well known in the art. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, etc. The silicon-based material may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based material may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, the present application is not limited to these materials, and other traditional materials that can be used as negative electrode active materials for batteries may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0124] In some embodiments, the material of the positive electrode current collector may be aluminum, and the material of the negative electrode current collector may be copper.

[0125] In some embodiments, the electrode assembly is a wound structure.

[0126] In some embodiments, the electrode assembly is a laminate structure.

[0127] Energy storage device 10 integrates multiple battery cells 21 within a housing 1. Multiple battery cells 21 are connected in series, parallel, or hybrid to store electrical energy. Energy storage device 10 can be used in power systems to store excess energy during off-peak periods to supplement peak demand.

[0128] The energy storage device 10 generally needs to be connected to the energy storage converter 20. External devices (such as the power grid) can convert electrical energy from AC to DC through the energy storage converter 20 and store it in the energy storage device 10 to charge the energy storage device 10. The energy storage device 10 can also convert electrical energy from DC to AC through the energy storage converter 20 to supply power to external devices to discharge the energy storage device 10. For general energy storage devices 10, the matching problem between the energy storage device 10 and the energy storage converter 20 is not considered, and sufficient power margin is not set for the energy storage device 10. After a short period of use, the capacity of the energy storage device 10 needs to be supplemented. For example, on the basis of the original energy storage device 10, some battery cells 21 are added to achieve the purpose of capacity supplement. This type of energy storage device 10 has poor power matching with the energy storage converter 20.

[0129] In view of this, an embodiment of the present application provides an energy storage device 10 for electrically connecting to an energy storage converter 20. The energy storage converter 20 can be used to cooperate with M energy storage devices 10, where M is a positive integer, the rated output power of the energy storage converter 20 is P, in W, the energy of the energy storage device 10 is Q, in Wh, and the time it takes for the energy storage device 10 to discharge from a fully charged state to a fully discharged state is A, in h. P / (M*Q / A) is set within the range of 0.7 to 0.99. In this way, the long-term reliability and economy of the energy storage device 10 are taken into account, and the power matching between the energy storage device 10 and the energy storage converter 20 is improved.

[0130] The energy storage device 10 described in the embodiment of the present application is applicable to an energy storage system 100 .

[0131] Please refer to Figure 1, which is a schematic block diagram of an energy storage system 100 provided in some embodiments of the present application. The energy storage system 100 may include an energy storage device 10 and a power conversion system (PCS) 20, and the energy storage device 10 is electrically connected to the power conversion system 20.

[0132] The energy storage converter 20 is a device that connects external equipment to the energy storage device 10. The external equipment can be a power grid, an electrical device, etc. The energy storage converter 20 has a DC side and an AC side. The DC side is used to electrically connect to the energy storage device 10, and the AC side is used to connect to external equipment.

[0133] When the energy storage device 10 is in the charging state, the energy storage converter 20 acts as a rectifier to convert the electrical energy from the AC power on the AC side into DC power and stores it in the energy storage device 10. When the energy storage device 10 is in the discharging state, the energy storage converter 20 acts as an inverter to convert the electrical energy stored in the energy storage device 10 from the DC power on the DC side into AC power and transmits it to external equipment.

[0134] In the energy storage system 100, one energy storage converter 20 may correspond to one energy storage device 10, or may correspond to multiple energy storage devices 10. In embodiments where one energy storage converter 20 corresponds to multiple energy storage devices 10, the number of energy storage devices 10 may be two, three, four, five, six, seven, eight, or more. As an example, in FIG1 , one energy storage converter 20 is electrically connected to four energy storage devices 10.

[0135] The specific structure of the energy storage device 10 provided in the embodiment of the present application is described in detail below with reference to the accompanying drawings.

[0136] Please refer to Figure 2, which is an axonometric view of the energy storage device 10 provided in some embodiments of the present application. The embodiments of the present application provide an energy storage device 10 for electrically connecting to an energy storage converter 20. The energy storage converter 20 can be used to cooperate with M energy storage devices 10, where M is a positive integer, the rated output power of the energy storage converter 20 is P, in W, the energy of the energy storage device 10 is Q, in Wh, and the time it takes for the energy storage device 10 to discharge from a fully charged state to a fully discharged state is A, in h, satisfying the following: 0.7≤P / (M*Q / A)≤0.99.

[0137] The rated output power of the energy storage converter 20 is the rated output power of the AC side of the energy storage converter 20. The rated output power of the energy storage converter 20 is represented by P, in watts, abbreviated as "W," with the symbol "W." The energy of the energy storage device 10 is represented by Q, in watt-hours, with the symbol "Wh." The duration of the energy storage device 10 discharging from a fully charged state to a fully discharged state is represented by A, in hours, with the symbol "h."

[0138] It is understood that when the energy storage device 10 is fully charged, it is in the fully charged state; when the energy storage device 10 is completely discharged, it is in the fully discharged state. The time it takes for the energy storage device 10 to discharge from the fully charged state to the fully discharged state through the energy storage converter 20 is represented by A, with the unit being "hours" and the symbol being "h".

[0139] M can be 1, 2, 3, 4, 5, 6, 7, 8, etc. M can be equal to A, or M can be greater than A, or M can be less than A.

[0140] M*Q represents the total energy of the M energy storage devices 10 coordinated with the energy storage converter 20 , and M*Q / A represents the power of the M energy storage devices 10 coordinated with the energy storage converter 20 .

[0141] P / (M*Q / A) can be any one of 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 0.99, etc., or a range of values ​​between any two of them.

[0142] In the embodiment of the present application, P / (M*Q / A) ≤ 0.99, so that the power of all energy storage devices 10 cooperating with the energy storage converter 20 has sufficient margin compared to the power of the energy storage converter 20, and there is no need to increase the capacity of the energy storage device 10 for a long time, thereby achieving long-term reliability of the energy storage device 10; P / (M*Q / A) ≥ 0.7, so that the power margin of the energy storage device 10 compared to the power of the energy storage converter 20 is not too large, reducing power waste and improving the economic efficiency of the energy storage device 10. In this way, from the perspective of the long-term reliability and economic efficiency of the energy storage device 10, the power matching between the energy storage device 10 and the energy storage converter 20 is improved.

[0143] The following is a detailed description based on experimental data:

[0144] Table 1

[0145] According to Table 1 above, by comparing Examples 1-9 with Comparative Example 1, it can be seen that when P / (M*Q / A) ≤ 0.99, the capacity replenishment cycle of the energy storage device 10 is longer, and the capacity of the energy storage device 10 does not need to be replenished in a short period of time, thereby achieving long-term reliability of the energy storage device 10.

[0146] In some embodiments, 0.75≤P / (M*Q / A)≤0.95.

[0147] In this embodiment, P / (M*Q / A) can be any point value among 0.75, 0.78, 0.8, 0.83, 0.85, 0.88, 0.9, 0.93, 0.95, etc., or a range value between any two of them.

[0148] In this embodiment, 0.75≤P / (M*Q / A)≤0.95, which takes into account both the long-term reliability and economy of the energy storage device 10 , and can control the cost of the energy storage device 10 at a low level while increasing the capacity replenishment cycle of the energy storage device 10 .

[0149] In some embodiments, 0.85≤P / (M*Q / A)≤0.93.

[0150] In this embodiment, P / (M*Q / A) can be any point value among 0.85, 0.86, 0.87, 0.88, 0.89, 0.9, 0.91, 0.92, 0.93, etc., or a range value between any two of them.

[0151] In this embodiment, 0.85≤P / (M*Q / A)≤0.93, which further takes into account the long-term reliability and economy of the energy storage device 10, can further control the cost of the energy storage device 10 at a lower level, and can further increase the capacity replenishment cycle of the energy storage device 10.

[0152] In some embodiments, please refer to Figures 3 to 6. Figure 3 is a structural schematic diagram of the energy storage device 10 provided in some embodiments of the present application; Figure 4 is a structural schematic diagram of the box body 1 shown in Figure 3; Figure 5 is an AA cross-sectional view of the box body 1 shown in Figure 4; and Figure 6 is an exploded view of the battery 2 shown in Figure 3. The energy storage device 10 includes a box body 1 and at least one battery 2. The box body 1 includes a battery compartment 11. At least one battery 2 is accommodated in the battery compartment 11. The battery 2 includes at least one battery cell 21. The capacity of the battery cell 21 is C, in Ah. The platform voltage of the battery cell 21 is U0, in V. The total number of battery cells 21 in the battery compartment 11 is N, and Q = N*C*U0.

[0153] The capacity of a battery cell 21 is represented by C, in ampere-hours (Ah). The plateau voltage of a battery cell 21 is represented by U0, in volts (V), with the symbol "V." The plateau voltage is the voltage at which the battery cell 21 experiences minimal voltage change and significant capacity change.

[0154] The housing 1 can be a standard component that meets the international standards established by the International Organization for Standardization (ISO), or a non-standard component. The housing 1 can also be referred to as a container, and the energy storage device 10 can also be referred to as an energy storage container. The housing 1 can have various shapes, such as a cylinder or a prism. As an example, in FIG3 , the housing 1 is in the shape of a quadrangular prism. Specifically, the housing 1 is in the shape of a rectangular parallelepiped.

[0155] The battery compartment 11 is a space inside the box body 1 for accommodating the battery 2. The battery compartment 11 can accommodate only the battery 2, or it can accommodate other components in addition to the battery 2, such as fire-fighting components. The fire-fighting components may include pipes, detectors, etc. The battery compartment 11 may be in various shapes, such as cylindrical, prism-shaped, etc. The prism may be a triangular prism, a quadrangular prism, a pentagonal prism, a hexagonal prism, etc. As an example, in Figures 3 to 5, the battery compartment 11 is in the shape of a quadrangular prism, and specifically, the battery 2 is in the shape of a rectangular parallelepiped. Taking the rectangular shape of the battery compartment 11 as an example, an opening is formed on at least one side of the battery compartment 11 along the width direction Y of the box body, and the battery 2 can enter the battery compartment 11 through the opening. A door leaf can be correspondingly provided on the opening side of the battery compartment 11. The door leaf can be slidably connected to the box body 1, hinged, etc., so as to open or close the opening by sliding or rotating.

[0156] The housing 1 may only have a battery compartment 11, or it may also have space for accommodating other components in addition to the battery compartment 11. For example, the housing 1 may further include a thermal management compartment 12 and a main control compartment 13. The thermal management compartment 12 may house a water cooling unit that provides a fluid medium for the thermal management component, which may be a water-cooled plate disposed within the battery compartment 11 for managing the temperature of the battery cells 21. The main control compartment 13 may house a main control unit that is used for high-voltage control and communication of the multiple battery cells 21 within the battery compartment 11. The housing 1 is rectangular in shape, with the battery compartment 11 and the main control compartment 13 arranged along the height direction Z of the housing. The thermal management compartment 12 may be located on one side of the battery compartment 11 along the length direction X of the housing, and the main control compartment 13 may be located at the bottom of the battery compartment 11 along the height direction Z of the housing. In other embodiments, the housing 1 may further include an electrical compartment 14 that may house a busbar unit, a power distribution unit, and a control unit. The confluence unit is used to achieve the confluence of multiple batteries 2, ensuring a secure connection between the multiple batteries 2 and the DC side of the energy storage converter 20. The power distribution unit can draw power from the grid to power the internal control system and auxiliary systems. The control unit may include a battery cell 21 management unit, a fire control unit, etc., for monitoring and managing the internal structure of the energy storage device 10. The electrical compartment 14 and the thermal management compartment 12 can be located on one side of the battery compartment 11 along the longitudinal direction X of the box, and the electrical compartment 14 and the thermal management compartment 12 are arranged along the width direction Y of the box.

[0157] The battery 2 in the battery compartment 11 can be one or more batteries 2, and the battery cells 21 in the battery 2 can be one or more. The batteries 2 in the battery compartment 11 can be connected in series, in parallel, or in a hybrid connection, and the battery cells 21 in the battery 2 can also be connected in series, in parallel, or in a hybrid connection. Hybrid connection refers to both series and parallel connection.

[0158] It is understood that if the battery cells 21 in each battery 2 are equal, the number N of battery cells 21 in the battery compartment 11 is equal to the number of batteries 2 in the battery compartment 11 multiplied by the number of battery cells 21 in the battery 2. If there is one battery 2 in the battery compartment 11 and one battery cell 21 in the battery 2, the battery compartment 11 only accommodates one battery cell 21, and N=1.

[0159] Along the length direction X of the case, the battery compartment 11 can accommodate one battery 2 or multiple batteries 2; along the width direction Y of the case, the battery compartment 11 can accommodate one battery 2 or multiple batteries 2; along the height direction of the case 1, the battery compartment 11 can accommodate one battery 2 or multiple batteries 2. The battery 2 can be rectangular. After the battery 2 is accommodated in the battery compartment 11, one of the length direction, width direction, and height direction of the battery 2 can be parallel to the length direction X of the case, another can be parallel to the width direction Y of the case, and another can be parallel to the height direction Z of the case. As an example, in the embodiment shown in Figure 3, along the length direction X of the case, the battery compartment 11 accommodates multiple batteries 2; along the height direction Z of the case, the battery compartment 11 accommodates multiple batteries 2; along the width direction Y of the case, the battery compartment 11 accommodates only one battery 2, the length direction of the battery 2 is parallel to the width direction Y of the case, the width direction of the battery 2 is parallel to the length direction X of the case, and the height direction of the battery 2 is parallel to the height direction Z of the case.

[0160] In this embodiment, Q = N*C*U0, ensuring that all battery cells 21 in the battery compartment 11 have equal capacity and can use battery cells 21 of the same specifications. This improves the assembly efficiency of the energy storage device 10 and reduces the possibility of wasted space due to different specifications of battery cells 21 in the battery compartment 11.

[0161] In some embodiments, the battery 2 may be a battery module. For example, the battery 2 may include multiple battery cells 21, which are arranged and fixed to form a battery module. In the battery module, a frame may be formed by two side plates and two end plates, and the battery cells 21 may be fixed within the frame to form the battery module.

[0162] In other embodiments, as shown in FIG6 , the battery 2 may also be a battery pack, and the battery 2 may further include a battery box 22 , in which the battery cells 21 are accommodated. If there are multiple battery cells 21 in the battery 2, the multiple battery cells 21 may be arranged in an array in the battery box 22. The battery box 22 may include a first portion 221 and a second portion 222 , and the first portion 221 and the second portion 222 cover each other to define a storage space for accommodating the battery cells 21. The first portion 221 and the second portion 222 may be in various shapes, such as a rectangular parallelepiped, a cylindrical shape, etc. The first portion 221 may be a hollow structure with one side open, and the second portion 222 may also be a hollow structure with one side open. The open side of the second portion 222 covers the open side of the first portion 221 to form a battery box 22 with a storage space. Alternatively, the first portion 221 may be a hollow structure with one side open, and the second portion 222 may be a plate-like structure, with the second portion 222 covering the open side of the first portion 221, thereby forming a battery box 22 having a storage space. The first portion 221 and the second portion 222 may be sealed by a sealing element, which may be a sealing ring, sealant, or the like.

[0163] In some embodiments, referring to FIG7 , FIG7 is an exploded view of the battery cell 21 shown in FIG6 . The battery cell 21 may include a housing 211 , an electrode assembly 213 , and an electrode terminal 212 . The electrode terminal 212 is disposed on the housing 211 and is electrically connected to the electrode assembly 213 .

[0164] The housing 211 is a component used to house the electrode assembly 213 and electrolyte. The housing 211 can be cylindrical or prismatic. Prisms include triangular prisms, quadrangular prisms, pentagonal prisms, and hexagonal prisms. Quadrangular prisms include oblique quadrangular prisms and right parallelepipeds. Right parallelepipeds include cuboids and cubes. For example, the housing 211 can include a shell 2111 and an end cap 2112.

[0165] The housing 2111 can be a hollow structure with an opening at one end, or a hollow structure with openings at opposite ends. The housing 2111 can have various shapes, such as a cylinder or a prism. The housing 2111 can be made of various materials, such as copper, iron, aluminum, steel, aluminum alloy, plastic, etc.

[0166] The end cap 2112 is a component that closes the opening of the shell 2111 to isolate the internal environment of the battery cell 21 from the external environment. The end cap 2112 and the shell 2111 together define a storage space for accommodating the electrode assembly 213, electrolyte and other components. The shape of the end cap 2112 can be adapted to the shape of the shell 211. For example, the shell 2111 is a rectangular parallelepiped structure, and the end cap 2112 is a rectangular plate structure adapted to the shell 2111. For another example, the shell 2111 is a cylindrical structure, and the end cap 2112 is a circular plate structure adapted to the shell 2111. The material of the end cap 2112 can also be a variety of materials, such as copper, iron, aluminum, steel, aluminum alloy, plastic, etc. The material of the end cap 2112 and the shell 2111 can be the same or different.

[0167] In an embodiment where the housing 2111 is open at one end, one end cap 2112 may be provided. In an embodiment where the housing 2111 is open at two opposite ends, two end caps 2112 may be provided, each of which closes the two openings of the housing 2111, and the two end caps 2112 and the housing 2111 together define a receiving space.

[0168] The electrode terminals 212 are components within the battery cell 21 that input or output electrical energy. They are located on the outer casing 211 and are used to electrically connect to the tabs 2131 of the electrode assembly 213. The electrode terminals 212 can be located on the housing 2111 of the outer casing 211 or on the end caps 2112 of the outer casing 211. The electrode terminals 212 and tabs 2131 can be connected directly, for example, by direct welding. Alternatively, they can be connected indirectly via current collecting components, which can be metal conductors such as copper, iron, aluminum, steel, or aluminum alloys.

[0169] As an example, as shown in Figure 7, the shell 2111 is a hollow structure with an opening formed at one end. There is only one end cover 2112 in the shell 211, and the end cover 2112 closes the opening of the shell 2111. Two electrode terminals 212 are provided on the end cover 2112. The electrode terminals 212 partially protrude from the outer surface of the end cover 2112. A positive electrode ear 2131 and a negative electrode ear 2131 are formed on the end of the electrode assembly 213 facing the end cover 2112. The positive electrode ear 2131 and the negative electrode ear 2131 are electrically connected to the two electrode terminals 212, respectively.

[0170] Taking the rectangular outer shell 211 of the battery cell 21 as an example, the outer shell 211 has a length, a width, and a height. The length of the outer shell 211 is greater than or equal to the width of the outer shell 211, and the electrode terminal 212 is located at one end of the outer shell 211 in the height direction. After the battery 2 is accommodated in the battery compartment 11, one of the length, width, and height directions of the outer shell 211 can be parallel to the length direction X of the compartment, another can be parallel to the width direction Y of the compartment, and another can be parallel to the height direction Z of the compartment.

[0171] In some embodiments, please refer to Figures 8-10. Figure 8 is a diagram illustrating the arrangement of batteries 2 within the battery compartment 11 shown in Figure 3; Figure 9 is a diagram illustrating the arrangement of batteries 2 within the battery compartment 11 provided in other embodiments of the present application; Figure 10 is a schematic diagram illustrating the structure of batteries 2 provided in some embodiments of the present application; and Figure 11 is a schematic diagram illustrating the structure of batteries 2 provided in other embodiments of the present application. The battery compartment 11 accommodates N1 batteries 2, wherein the N1 batteries 2 are formed by X1 first battery groups 2a connected in parallel, each first battery group 2a being formed by Y1 batteries 2 connected in series; or, the N1 batteries 2 are formed by Y1 second battery groups 2b connected in series, each second battery group 2b being formed by X1 batteries 2 connected in parallel, satisfying the following: N1 ≥ 1, X1 ≥ 1, Y1 ≥ 1, and N1 = X1 * Y1. The battery 2 includes N2 battery cells 21, where the N2 battery cells 21 are formed by X2 first battery cell groups 21a connected in parallel, and each first battery cell group 21a is formed by Y2 battery cells 21 connected in series; or, the N2 battery cells 21 are formed by Y2 second battery cell groups 21b connected in series, and each second battery cell group 21b is formed by X2 battery cells 21 connected in parallel, satisfying: N2 ≥ 1, X2 ≥ 1, Y2 ≥ 1, N2 = X2 * Y2, N = N1 * N2.

[0172] X1 is the number of batteries 2 connected in parallel within the battery compartment 11, and Y1 is the number of batteries 2 connected in series within the battery compartment 11. X2 is the number of battery cells 21 connected in parallel within the battery compartment 11, and Y2 is the number of battery cells 21 connected in series within the battery compartment 11. N1, N2, X2, and Y2 are integers greater than or equal to 1.

[0173] If X1 = 1, N1 batteries 2 formed from X1 first battery groups 2a connected in parallel are equivalent to N1 batteries 2 formed from one first battery group 2a; each second battery group 2b formed from X1 batteries 2 connected in parallel is equivalent to each second battery group 2b formed from one battery 2. If Y1 = 1, each first battery group 2a formed from Y1 batteries 2 connected in series is equivalent to each first battery group 2a formed from one battery 2; N1 batteries 2 formed from Y1 second battery groups 2b connected in series is equivalent to N1 batteries 2 formed from one second battery group 2b.

[0174] If X2 = 1, N2 battery cells 21 formed by X2 first battery cell groups 21a connected in parallel are equivalent to N2 battery cells 21 formed by one first battery cell group 21a; each second battery cell group 21b formed by X2 battery cells 21 connected in parallel is equivalent to each second battery cell group 21b formed by one battery cell 21. If Y2 = 1, each first battery cell group 21a formed by Y2 battery cells 21 connected in series is equivalent to each first battery cell group 21a formed by one battery cell 21; N2 battery cells 21 formed by Y2 second battery cell groups 21b connected in series is equivalent to N2 battery cells 21 formed by one second battery cell group 21b.

[0175] 8 , N1 batteries 2 are formed by X1 first battery groups 2a connected in parallel, and each first battery group 2a is formed by Y1 batteries 2 connected in series. As an example, X1=4, Y1=8.

[0176] 9 , N1 batteries 2 are formed by Y1 second battery groups 2 b connected in series, and each second battery group 2 b is formed by X1 batteries 2 connected in parallel. As an example, X1=4, Y1=8.

[0177] In the embodiment shown in Figure 10, N2 battery cells 21 are formed by X2 first battery cell groups 21a connected in parallel, and each first battery cell group 21a is formed by Y2 battery cells 21 connected in series. There are multiple battery cells 21 within the battery box 22, and the multiple battery cells 21 are arranged in an array, with each row of battery cells 21 arranged along the length direction X of the box, and each column of battery cells 21 arranged along the width direction Y of the box. As an example, all battery cells 21 in every two columns of battery cells 21 are connected in series to form a first battery cell group 21a. Specifically, the battery cells 21 within the battery box 22 are arranged in 26 rows and 4 columns, with X2 = 2 and Y2 = 52.

[0178] In the embodiment shown in Figure 11, N2 battery cells 21 are formed by Y2 second battery cell groups 21b connected in series, each of which is formed by X2 battery cells 21 connected in parallel. The battery case 22 contains multiple battery cells 21, which are arranged in an array. Each row of battery cells 21 is arranged along the length direction X of the case, and each column of battery cells 21 is arranged along the width direction Y of the case. As an example, in each column of battery cells 21, every two battery cells 21 are connected in parallel to form a second battery cell group 21b. Specifically, the battery cells 21 in the battery case 22 are arranged in 26 rows and 4 columns, with X2 = 2 and Y2 = 52.

[0179] In this embodiment, for the N1 batteries 2 in the battery compartment 11, Y1 batteries 2 can be connected in series to form a first battery group 2a, and then X1 first battery groups 2a can be connected in parallel; or X1 batteries 2 can be connected in parallel to form a second battery group 2b, and then Y1 second battery groups 2b can be connected in series. For the N2 battery cells 21 in the battery 2, Y2 battery cells 21 can be connected in series to form a first battery group 21a, and then X2 first battery groups 21a can be connected in parallel; or X2 battery cells 21 can be connected in parallel to form a second battery group 21b, and then Y2 second battery groups 21b can be connected in series. The number Y1 of batteries 2 in the battery compartment 11 and the number Y2 of battery cells 21 in the battery 2 can be set as needed to adjust the voltage of the energy storage device 10 to a reasonable range.

[0180] In some embodiments, when the energy storage device 10 is charged, the maximum operating voltage of the DC side of the energy storage converter 20 is U1, and the minimum operating voltage of the DC side of the energy storage converter 20 is U2, satisfying: U2<U0*Y1*Y2<U1.

[0181] When an external device charges the energy storage device 10 through the energy storage converter 20, the operating voltage on the DC side of the energy storage converter 20 gradually changes with the charging status of the energy storage device 10. For example, the operating voltage on the DC side of the energy storage converter 20 gradually increases. U1 is the maximum operating voltage of the energy storage converter 20 during charging, and U2 is the minimum operating voltage of the energy storage converter 20 during charging.

[0182] Wherein, U0*Y1*Y2 is the voltage of the energy storage device 10 .

[0183] In this embodiment, U0*Y1*Y2<U1, which enables the external device to charge the energy storage device 10 normally through the energy storage converter 20; U0*Y1*Y2>U2, which enables the energy storage device 10 to supply power to the external device through the energy storage converter 20. Therefore, U0*Y1*Y2 is controlled within the range of U2 to U1, so that the voltage of the energy storage converter 20 is compatible with the voltage of the energy storage converter 20. This allows both the external device to charge the energy storage device 10 through the energy storage converter 20 and the energy storage device 10 to supply power to the external device through the energy storage converter 20.

[0184] In some embodiments, the positive electrode material of the battery cell 21 includes lithium-containing phosphate, 2.8V≤U0≤3.6V, 250≤Y1*Y2≤468.

[0185] Lithium-containing phosphates include but are not limited to: at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon.

[0186] In this embodiment, U0 can be any value among 2.8V, 2.9V, 3V, 3.1V, 3.2V, 3.3V, 3.4V, 3.5V, 3.6V, etc., or a range between any two values. Y1*Y2 can be any value among 250, 256, 280, 288, 300, 304, 320, 336, 360, 384, 400, 416, 440, 468, etc., or a range between any two values.

[0187] In this embodiment, when the positive electrode material of the battery cell 21 includes lithium phosphate, 2.8V≤U0≤3.6V, 250≤Y1*Y2≤468, the voltage of the energy storage converter 20 can be controlled within a reasonable range, so that the voltage of the energy storage device 10 is not too low, and the energy storage device 10 can be adapted to the energy storage converter 20 with a higher operating voltage, and the voltage of the energy storage device 10 is not too high, thereby reducing the requirements for the operating voltage of the energy storage converter 20 and reducing production costs.

[0188] In some embodiments, the positive electrode material of the battery cell 21 includes lithium iron phosphate, 3.1V≤U0≤3.3V, 400≤Y1*Y2≤424.

[0189] In this embodiment, U0 can be any value among 3.1V, 3.13V, 3.15V, 3.18V, 3.2V, 3.23V, 3.25V, 3.28V, 3.3V, etc., or a range between any two values. Y1*Y2 can be any value among 400, 404, 408, 412, 416, 420, 424, etc., or a range between any two values.

[0190] In this embodiment, when the positive electrode material of the battery cell 21 includes lithium iron phosphate, 3.1V≤U0≤3.3V, 400≤Y1*Y2≤424, and the voltage of the energy storage converter 20 can be controlled within a reasonable range.

[0191] In some embodiments, 3.5*10 6 W≤P≤7.5*10 6 W, M = A, 1≤X1*X2≤18.

[0192] P can be 3.5*10 6 W, 3.75*10 6 W, 4*106 W, 4.2*10 6 W, 4.5*10 6 W, 4.9*10 6 W, 5*10 6 W, 5.2*10 6 W, 5.5*10 6 W, 5.8*10 6 W, 6*10 6 W, 6.2*10 6 W, 6.8*10 6 W, 7*10 6 W, 7.2*10 6 W, 7.5*10 6 Any point value of W, etc. or a range of values ​​between any two. X1*X2 can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18.

[0193] In this embodiment, the positive electrode material of the battery cell 21 includes lithium phosphate, 3.5*10 6 W≤P≤7.5*10 6 W, and when M=A, X1*X2 can be set in the range of 1 to 18 to control the capacity of the battery cell 21 within a reasonable range.

[0194] In some embodiments, X1=1.

[0195] It is understandable that in an embodiment where a plurality of batteries 2 are accommodated in the battery compartment 11 , all the batteries 2 in the battery compartment 11 are connected in series.

[0196] In this embodiment, the positive electrode material of the battery cell 21 includes lithium-containing phosphate, and X2 can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18.

[0197] In some embodiments, X2=1, 2000Ah≤C≤11000Ah.

[0198] In this embodiment, X1=1, X2=1, and C can be any point value of 2000Ah, 3000Ah, 4000Ah, 5000Ah, 6000Ah, 7000Ah, 8000Ah, 9000Ah, 10000Ah, 11000Ah, etc., or a range value between any two of them.

[0199] In this embodiment, when the positive electrode material of the battery cell 21 includes lithium phosphate, and the parallel number X1 of the batteries 2 in the battery compartment 11 and the parallel number X2 of the battery cells 21 of the battery 2 are both 1, the capacity of the battery cell 21 is set within the range of 2000Ah to 11000Ah, which can meet both the power matching requirements and the voltage requirements of the energy storage device 10.

[0200] In some embodiments, 2500Ah≤C≤6000Ah.

[0201] In this embodiment, X1 = 1, and X2 = 1. C can be any one of 2500Ah, 2800Ah, 3000Ah, 3300Ah, 3500Ah, 3800Ah, 4000Ah, 4300Ah, 4500Ah, 4800Ah, 5000Ah, 5300Ah, 5500Ah, 5800Ah, 6000Ah, etc., or a range of values ​​between any two of them.

[0202] In some embodiments, X2=2, 1000Ah≤C≤5500Ah.

[0203] In this embodiment, X1 = 1, and X2 = 2. C can be any point value among 1000Ah, 1500Ah, 2000Ah, 2500Ah, 3000Ah, 3500Ah, 4000Ah, 4500Ah, 5000Ah, etc., or a range of values ​​between any two of them.

[0204] When the positive electrode material of the battery cell 21 includes lithium phosphate, the parallel number X1 of the battery 2 in the battery compartment 11 is 1, and the parallel number X2 of the battery cells 21 of the battery 2 is 2, the capacity of the battery cell 21 is set within the range of 1000Ah to 5500Ah, which can meet both the power matching requirements of the energy storage device 10 and the voltage requirements of the energy storage device 10.

[0205] In some embodiments, 2000 Ah ≤ C ≤ 4000 Ah.

[0206] In this embodiment, X1 = 1, and X2 = 2. C can be any one of 2000Ah, 2100Ah, 2200Ah, 2300Ah, 2400Ah, 2500Ah, 2600Ah, 2700Ah, 2800Ah, 2900Ah, 3000Ah, 3100Ah, 3200Ah, 3300Ah, 3400Ah, 3500Ah, 3600Ah, 3700Ah, 3800Ah, 3900Ah, 4000Ah, etc., or a range of values ​​between any two of them.

[0207] In some embodiments, 2≤X1≤6.

[0208] In this embodiment, X1 can be 2, 3, 4, 5, or 6.

[0209] In this embodiment, the positive electrode material of the battery cell 21 includes lithium phosphate, which controls the parallel number X1 of the batteries 2 in the battery compartment 11 within a reasonable range, X1 ≥ 2, so that the capacity of the battery cell 21 is not too large, reducing the manufacturing difficulty and manufacturing cost of the battery cell 21, and X1 ≤ 6 so that the parallel number X1 of the batteries 2 in the battery compartment 11 is not too large, which is beneficial to improving the space utilization of the battery compartment 11.

[0210] In some embodiments, X1=4, X2=1, 500Ah≤C≤2600Ah.

[0211] In this embodiment, C can be any point value of 500Ah, 800Ah, 1000Ah, 1300Ah, 1500Ah, 1800Ah, 2000Ah, 2300Ah, 2500Ah, 2600Ah, etc., or a range value between any two of them.

[0212] In this embodiment, when the positive electrode material of the battery cell 21 includes lithium-containing phosphate, and X1=4, X2=1, the capacity of the battery cell 21 is set within the range of 500Ah to 2600Ah, which can meet both the power matching requirements and the voltage requirements of the energy storage device 10.

[0213] In some embodiments, 800Ah≤C≤1500Ah.

[0214] In this embodiment, X1=4, X2=1, and C can be any point value of 800Ah, 900Ah, 1000Ah, 1100Ah, 1200Ah, 1300Ah, 1400Ah, 1500Ah, etc., or a range value between any two of them.

[0215] In some embodiments, X1=4, X2=2, 250Ah≤C≤1300Ah.

[0216] In this embodiment, C can be any point value of 250Ah, 300Ah, 400Ah, 500Ah, 600Ah, 700Ah, 800Ah, 900Ah, 1000Ah, 1100Ah, 1200Ah, 1300Ah, etc., or a range value between any two of them.

[0217] In this embodiment, when the positive electrode material of the battery cell 21 includes lithium-containing phosphate, and X1=4, X2=2, the capacity of the battery cell 21 is set within the range of 800Ah to 1500Ah, which can meet both the power matching requirements and the voltage requirements of the energy storage device 10.

[0218] In some embodiments, 350Ah≤C≤1000Ah.

[0219] In this embodiment, the positive electrode material of the battery cell 21 includes lithium phosphate, X1=4, X2=2, and C can be any point value of 350Ah, 400Ah, 450Ah, 500Ah, 550Ah, 600Ah, 650Ah, 700Ah, 750Ah, 800Ah, 850Ah, 900Ah, 950Ah, 1000Ah, etc., or a range value between any two of them.

[0220] In some embodiments, 500Ah≤C≤700Ah.

[0221] In this embodiment, the positive electrode material of the battery cell 21 includes lithium phosphate, X1=4, X2=2, and C can be any point value of 500Ah, 530Ah, 550Ah, 580Ah, 588Ah, 600Ah, 630Ah, 650Ah, 680Ah, 700Ah, etc., or a range value between any two of them.

[0222] In some embodiments, the positive electrode material of the battery cell 21 includes lithium transition metal oxide, 2.8V≤U0≤4.35V, 210≤Y1*Y2≤530.

[0223] Lithium transition metal oxides include but are not limited to lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also referred to as NCM 333 ), LiNi 0.5 Co 0.2 Mn 0.3 O2 (also referred to as NCM 523 ), LiNi 0.5 Co 0.25 Mn 0.25 O2 (also referred to as NCM 211 ), LiNi 0.6 Co 0.2 Mn 0.2O2 (also referred to as NCM 622 ), LiNi 0.8 Co 0.1 Mn 0.1 O2 (also referred to as NCM 811 ), lithium nickel cobalt aluminum oxide (such as LiNi 0.85 Co 0.15 Al 0.05 O2) and at least one of its modified compounds, etc.

[0224] In this embodiment, U0 can be any value among 2.8V, 2.9V, 3V, 3.1V, 3.2V, 3.3V, 3.4V, 3.5V, 3.6V, 3.7V, 3.8V, 3.9V, 4V, 4.1V, 4.2V, 4.3V, 4.35V, etc., or a range between any two of them. Y1*Y2 can be any value among 210, 224, 240, 250, 256, 280, 288, 300, 304, 320, 336, 360, 384, 400, 416, 440, 468, 480, 496, 512, 530, etc., or a range between any two of them.

[0225] In this embodiment, when the positive electrode material of the battery cell 21 includes lithium transition metal oxide, 2.8V≤U0≤4.35V, 210≤Y1*Y2≤530, the voltage of the energy storage converter 20 can be controlled within a reasonable range, so that the voltage of the energy storage device 10 is not too low, and the energy storage device 10 can be adapted to the energy storage converter 20 with a higher operating voltage, and the voltage of the energy storage device 10 is not too high, thereby reducing the requirements for the operating voltage of the energy storage converter 20 and reducing production costs.

[0226] In some embodiments, 3.5*10 6 W≤P≤7.5*10 6 W, M = A, 1≤X1*X2≤18.

[0227] In this embodiment, P can be 3.5*10 6 W, 3.75*10 6 W, 4*10 6 W, 4.2*10 6 W, 4.5*10 6 W, 4.9*10 6 W, 5*10 6 W, 5.2*10 6 W, 5.5*10 6 W, 5.8*10 6 W, 6*10 6 W, 6.2*10 6W, 6.8*10 6 W, 7*10 6 W, 7.2*10 6 W, 7.5*10 6 Any point value of W, etc. or a range of values ​​between any two. X1*X2 can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18.

[0228] In this embodiment, the positive electrode material of the battery cell 21 includes lithium transition metal oxide, 3.5*10 6 W≤P≤7.5*10 6 W, and when M=A, X1*X2 can be set in the range of 1 to 18 to control the capacity of the battery cell 21 within a reasonable range.

[0229] In some embodiments, X1=1.

[0230] In this embodiment, the positive electrode material of the battery cell 21 includes lithium transition metal oxide, and X2 can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18.

[0231] In some embodiments, X2=1, 1500 Ah≤C≤13400 Ah.

[0232] In this embodiment, X1=1, X2=1, and C can be any point value of 1500Ah, 1800Ah, 2000Ah, 3000Ah, 4000Ah, 5000Ah, 6000Ah, 7000Ah, 8000Ah, 9000Ah, 10000Ah, 11000Ah, 12000Ah, 13000Ah, 13400Ah, etc., or a range value between any two of them.

[0233] When the positive electrode material of the battery cell 21 includes lithium transition metal oxide, and the parallel number X1 of the batteries 2 in the battery compartment 11 and the parallel number X2 of the battery cells 21 of the battery 2 are both 1, the capacity of the battery cell 21 is set within the range of 1500Ah to 13400Ah Ah, which can meet the power matching requirements of the energy storage device 10 and the voltage requirements of the energy storage device 10.

[0234] In some embodiments, 3000Ah≤C≤7000Ah.

[0235] In this embodiment, the positive electrode material of the battery cell 21 includes a lithium transition metal oxide, X1 = 1, and X2 = 1. C can be any value among 3000Ah, 3300Ah, 3500Ah, 3800Ah, 4000Ah, 4300Ah, 4500Ah, 4800Ah, 5000Ah, 5300Ah, 5500Ah, 5800Ah, 6000Ah, 6300Ah, 6500Ah, 6800Ah, 7000Ah, etc., or a range between any two of them.

[0236] In some embodiments, X2=2, 750Ah≤C≤6670Ah.

[0237] In this embodiment, the positive electrode material of the battery cell 21 includes a lithium transition metal oxide, X1 = 1, and X2 = 2. C can be any value among 750Ah, 850Ah, 1000Ah, 1500Ah, 2000Ah, 2500Ah, 3000Ah, 3500Ah, 4000Ah, 4500Ah, 5000Ah, 5500Ah, 6000Ah, 6500Ah, 6670Ah, etc., or a range between any two of them.

[0238] When the positive electrode material of the battery cell 21 includes lithium transition metal oxide, the parallel number X1 of the battery 2 in the battery compartment 11 is 1, and the parallel number X2 of the battery cells 21 of the battery 2 is 2, the capacity of the battery cell 21 is set within the range of 750Ah to 6670Ah, which can meet both the power matching requirements of the energy storage device 10 and the voltage requirements of the energy storage device 10.

[0239] In some embodiments, 1800Ah≤C≤4000Ah.

[0240] In this embodiment, the positive electrode material of the battery cell 21 includes a lithium transition metal oxide, X1=1, and X2=2. C can be any value among 1800Ah, 1900Ah, 2000Ah, 2100Ah, 2200Ah, 2300Ah, 2400Ah, 2500Ah, 2600Ah, 2700Ah, 2800Ah, 2900Ah, 3000Ah, 3100Ah, 3200Ah, 3300Ah, 3400Ah, 3500Ah, 3600Ah, 3700Ah, 3800Ah, 3900Ah, 4000Ah, etc., or a range between any two values.

[0241] In some embodiments, 2≤X1≤6.

[0242] In this embodiment, X1 can be 2, 3, 4, 5, or 6.

[0243] In this embodiment, the positive electrode material of the battery cell 21 includes lithium transition metal oxide, which controls the parallel number X1 of the batteries 2 in the battery compartment 11 within a reasonable range, so that the capacity of the battery cell 21 is not too large, reducing the manufacturing difficulty and manufacturing cost of the battery cell 21, and the parallel number X1 of the batteries 2 in the battery compartment 11 is not too large, which is beneficial to improving the space utilization of the battery compartment 11.

[0244] In some embodiments, X1=4, X2=1, 375Ah≤C≤3300Ah.

[0245] In this embodiment, the positive electrode material of the battery cell 21 includes lithium transition metal oxide, and C can be any point value among 375Ah, 500Ah, 800Ah, 1000Ah, 1300Ah, 1500Ah, 1800Ah, 2000Ah, 2300Ah, 2500Ah, 2600Ah, 2800Ah, 3000Ah, 3150Ah, 3300Ah, etc., or a range value between any two of them.

[0246] In this embodiment, when the positive electrode material of the battery cell 21 includes lithium transition metal oxide, and X1=4, X2=1, the capacity of the battery cell 21 is set within the range of 375Ah to 3300Ah, which can meet both the power matching requirements and the voltage requirements of the energy storage device 10.

[0247] In some embodiments, 700Ah≤C≤1600Ah.

[0248] In this embodiment, the positive electrode material of the battery cell 21 includes lithium transition metal oxide, X1=4, X2=1, and C can be any point value of 700Ah, 800Ah, 900Ah, 1000Ah, 1100Ah, 1200Ah, 1300Ah, 1400Ah, 1500Ah, 1600Ah, etc., or a range value between any two of them.

[0249] In some embodiments, X1=4, X2=2, 200Ah≤C≤1600Ah.

[0250] In this embodiment, C can be any point value of 200Ah, 300Ah, 400Ah, 500Ah, 600Ah, 700Ah, 800Ah, 900Ah, 1000Ah, 1100Ah, 1200Ah, 1300Ah, 1400Ah, 1500Ah, 1600Ah, etc., or a range value between any two of them.

[0251] In this embodiment, when the positive electrode material of the battery cell 21 includes lithium transition metal oxide, and X1=4, X2=2, the capacity of the battery cell 21 is set within the range of 200Ah to 1600Ah, which can meet both the power matching requirements and the voltage requirements of the energy storage device 10.

[0252] In some embodiments, 340Ah≤C≤1050Ah.

[0253] In this embodiment, the positive electrode material of the battery cell 21 includes lithium transition metal oxide, X1=4, X2=2, and C can be any point value of 340Ah, 400Ah, 450Ah, 500Ah, 550Ah, 600Ah, 650Ah, 700Ah, 750Ah, 800Ah, 850Ah, 900Ah, 950Ah, 1000Ah, 1050Ah, etc., or a range value between any two of them.

[0254] In some embodiments, 490Ah≤C≤720Ah.

[0255] In this embodiment, the positive electrode material of the battery cell 21 includes lithium transition metal oxide, X1=4, X2=2, and C can be any point value of 490Ah, 500Ah, 530Ah, 550Ah, 572Ah, 580Ah, 600Ah, 630Ah, 650Ah, 680Ah, 700Ah, 720Ah, etc., or a range value between any two of them.

[0256] In some embodiments, the battery cell 21 is a sodium ion battery cell, 1.5V≤U0≤4V, 230≤Y1*Y2≤1000.

[0257] In this embodiment, U0 can be any point value of 1.5V, 1.6V, 1.7V, 1.8V, 1.9V, 2V, 2.1V, 2.2V, 2.3V, 2.4V, 2.5V, 2.6V, 2.7V, 2.8V, 2.9V, 3V, 3.1V, 3.2V, 3.3V, 3.4V, 3.5V, 3.6V, 3.7V, 3.8V, 3.9V, 4V, etc., or a range value between any two of them. Y1*Y2 can be any one of the point values ​​of 230, 240, 250, 256, 280, 288, 300, 304, 320, 336, 360, 384, 400, 416, 440, 468, 480, 496, 512, 530, 560, 600, 640, 680, 720, 760, 800, 840, 880, 920, 960, 1000, etc., or a range of values ​​between any two of them.

[0258] When the battery cell 21 is a sodium ion battery cell, 1.5V≤U0≤4V, 230≤Y1*Y2≤1000, the voltage of the energy storage converter 20 can be controlled within a reasonable range, so that the voltage of the energy storage device 10 is not too low, and the energy storage device 10 can be adapted to the energy storage converter 20 with a higher operating voltage, and the voltage of the energy storage device 10 is not too high, thereby reducing the requirements for the operating voltage of the energy storage converter 20 and reducing production costs.

[0259] In some embodiments, 3.5*10 6 W≤P≤7.5*10 6 W, M = A, 1≤X1*X2≤18.

[0260] In this embodiment, P can be 3.5*10 6 W, 3.75*10 6 W, 4*10 6 W, 4.2*10 6 W, 4.5*10 6 W, 4.9*10 6 W, 5*10 6 W, 5.2*10 6 W, 5.5*10 6 W, 5.8*10 6 W, 6*10 6 W, 6.2*10 6 W, 6.8*10 6 W, 7*10 6 W, 7.2*10 6 W, 7.5*10 6 Any point value of W, etc. or a range of values ​​between any two. X1*X2 can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18.

[0261] The battery cell 21 is a sodium ion battery cell, 3.5*10 6 W≤P≤7.5*10 6 W, and when M=A, X1*X2 can be set in the range of 1 to 18 to control the capacity of the battery cell 21 within a reasonable range.

[0262] In some embodiments, X1=1.

[0263] In this embodiment, the battery cell 21 is a sodium ion battery cell, and X2 can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18.

[0264] In some embodiments, X2=1, 1200Ah≤C≤18000Ah.

[0265] In this embodiment, X1=1, X2=1, and C can be any one of 1200Ah, 1500Ah, 1800Ah, 2000Ah, 3000Ah, 4000Ah, 5000Ah, 6000Ah, 7000Ah, 8000Ah, 9000Ah, 10000Ah, 11000Ah, 12000Ah, 13000Ah, 14000Ah, 15000Ah, 16000Ah, 17000Ah, 18000Ah, etc., or a range value between any two of them.

[0266] When the battery cell 21 is a sodium ion battery cell, and the parallel number X1 of the battery 2 in the battery compartment 11 and the parallel number X2 of the battery cell 21 of the battery 2 are both 1, the capacity of the battery cell 21 is set within the range of 1200Ah to 18000Ah, which can meet the power matching requirements of the energy storage device 10 and the voltage requirements of the energy storage device 10.

[0267] In some embodiments, 2000 Ah ≤ C ≤ 10000 Ah.

[0268] In this embodiment, the battery cell 21 is a sodium ion battery cell, X1 = 1, and X2 = 1. C can be any one of 2000Ah, 2300Ah, 2500Ah, 2800Ah, 3000Ah, 3300Ah, 3500Ah, 3800Ah, 4000Ah, 4300Ah, 4500Ah, 4800Ah, 5000Ah, 5300Ah, 5500Ah, 5800Ah, 6000Ah, 6300Ah, 6500Ah, 6800Ah, 7000Ah, 8000Ah, 9000Ah, 10000Ah, etc., or a range between any two of them.

[0269] In some embodiments, X2=2, 600Ah≤C≤9000Ah.

[0270] In this embodiment, the battery cell 21 is a sodium ion battery cell, X1 = 1, and X2 = 2. C can be any one of 600Ah, 650Ah, 700Ah, 750Ah, 850Ah, 1000Ah, 1500Ah, 2000Ah, 2500Ah, 3000Ah, 3500Ah, 4000Ah, 4500Ah, 5000Ah, 5500Ah, 6000Ah, 6500Ah, 7000Ah, 7500Ah, 8000Ah, 8500Ah, 9000Ah, etc., or a range between any two of the values.

[0271] When the battery cell 21 is a sodium ion battery cell, the parallel number X1 of the battery 2 in the battery compartment 11 is 1, and the parallel number X2 of the battery 21 of the battery 2 is 2, the capacity of the battery cell 21 is set within the range of 600Ah to 9000Ah, which can meet both the power matching requirements and the voltage requirements of the energy storage device 10.

[0272] In some embodiments, 1600Ah≤C≤4000Ah.

[0273] In this embodiment, the battery cell 21 is a sodium ion battery cell, X1 = 1, and X2 = 2. C can be any value among 1600Ah, 1700Ah, 1800Ah, 1900Ah, 2000Ah, 2100Ah, 2200Ah, 2300Ah, 2400Ah, 2500Ah, 2600Ah, 2700Ah, 2800Ah, 2900Ah, 3000Ah, 3100Ah, 3200Ah, 3300Ah, 3400Ah, 3500Ah, 3600Ah, 3700Ah, 3800Ah, 3900Ah, 4000Ah, etc., or a range between any two values.

[0274] In some embodiments, 2≤X1≤6.

[0275] In this embodiment, X1 can be 2, 3, 4, 5, or 6.

[0276] In this embodiment, the parallel number X1 of the batteries 2 in the battery compartment 11 is controlled within a reasonable range, which not only prevents the capacity of the battery cell 21 from being too large, reducing the manufacturing difficulty and manufacturing cost of the battery cell 21, but also prevents the parallel number X1 of the batteries 2 in the battery compartment 11 from being too large, which is beneficial to improving the space utilization of the battery compartment 11.

[0277] In some embodiments, X1=4, X2=1, 300Ah≤C≤4000Ah.

[0278] In this embodiment, the battery cell 21 is a sodium ion battery cell, and C can be any one of 300Ah, 375Ah, 400Ah, 500Ah, 800Ah, 1000Ah, 1300Ah, 1500Ah, 1800Ah, 2000Ah, 2300Ah, 2500Ah, 2600Ah, 2800Ah, 3000Ah, 3150Ah, 3300Ah, 3500Ah, 3700Ah, 3900Ah, 4000Ah, etc., or a range value between any two of them.

[0279] When the battery cell 21 is a sodium ion battery cell, and X1=4, X2=1, the capacity of the battery cell 21 is set within the range of 300Ah to 4000Ah, which can meet both the power matching requirement and the voltage requirement of the energy storage device 10.

[0280] In some embodiments, 700Ah≤C≤1500Ah.

[0281] In this embodiment, the battery cell 21 is a sodium ion battery cell, X1=4, X2=1, and C can be any point value among 700Ah, 800Ah, 900Ah, 1000Ah, 1100Ah, 1200Ah, 1300Ah, 1400Ah, 1500Ah, etc., or a range value between any two of them.

[0282] In some embodiments, X1=4, X2=2, 150Ah≤C≤1500Ah.

[0283] In this embodiment, C can be any point value of 150Ah, 200Ah, 300Ah, 400Ah, 500Ah, 600Ah, 700Ah, 800Ah, 900Ah, 1000Ah, 1100Ah, 1200Ah, 1300Ah, 1400Ah, 1500Ah, etc., or a range value between any two of them.

[0284] When the battery cell 21 is a sodium ion battery cell, and X1=4, X2=2, the capacity of the battery cell 21 is set within the range of 150Ah to 1500Ah, which can meet both the power matching requirement and the voltage requirement of the energy storage device 10.

[0285] In some embodiments, 350Ah≤C≤1200Ah.

[0286] In this embodiment, the battery cell 21 is a sodium ion battery cell, X1=4, X2=2, and C can be any one of 350Ah, 400Ah, 450Ah, 500Ah, 550Ah, 600Ah, 650Ah, 700Ah, 750Ah, 800Ah, 850Ah, 900Ah, 950Ah, 1000Ah, 1050Ah, 1100Ah, 1200Ah, etc., or a range value between any two of them.

[0287] In some embodiments, 400Ah≤C≤650Ah.

[0288] In this embodiment, the battery cell 21 is a sodium ion battery cell, X1=4, X2=2, and C can be any one of 400Ah, 420Ah, 450Ah, 470Ah, 490Ah, 500Ah, 506Ah, 530Ah, 550Ah, 580Ah, 600Ah, 630Ah, 650Ah, etc., or a range value between any two of them.

[0289] In some embodiments, referring to FIG. 3 and FIG. 8 , X1 first battery packs 2 a are arranged along the length direction X of the box.

[0290] In this embodiment, the battery compartment 11 accommodates N1 batteries 2, which are formed by X1 first battery groups 2a connected in parallel, and each first battery group 2a is formed by Y1 batteries 2 connected in series. As an example, 2≤X1≤6.

[0291] It should be noted that no matter the battery cell 21 is a sodium ion battery 2, or the positive electrode material of the battery cell 21 includes lithium phosphate, or the positive electrode material of the battery cell 21 includes lithium transition metal oxide, X1 first battery groups 2a can be arranged along the length direction X of the box.

[0292] In this embodiment, X1 first battery packs 2a are arranged along the length direction X of the box. If X is set between 2 and 6, the space of the battery compartment 11 along the length direction X of the box can be fully utilized. The layout is reasonable, which is conducive to improving the space utilization of the battery compartment 11.

[0293] In some embodiments, please refer to Figures 12 to 14. Figure 12 is a schematic structural diagram of an energy storage device 10 provided in other embodiments of the present application;

[0294] Figure 13 is a schematic structural diagram of the housing 1 shown in Figure 12 , and Figure 14 is a cross-sectional view taken along line BB of the energy storage device 10 shown in Figure 12 . The battery compartment 11 includes a plurality of sub-compartments 111 arranged along the longitudinal direction X of the housing. Each sub-compartment 111 accommodates a first battery pack 2a along the longitudinal direction X of the housing.

[0295] The first battery group 2a in each sub-compartment 111 can also be called a battery cluster, and the number of battery clusters can be equal to the number of sub-compartments 111. During installation, Y1 batteries 2 can be accommodated in a sub-compartment 111 and connected in series to form a corresponding first battery group 2a.

[0296] There may be two, three, four, five, six, or more sub-compartments 111. Two adjacent sub-compartments 111 may be separated by a partition 112. The partition 112 may be a partition plate disposed between the two sub-compartments 111, or a partition beam disposed between the two sub-compartments 111. The partition beam may extend along the height direction Z of the box. When the partition 112 is a partition beam disposed between two adjacent sub-compartments 111, multiple partition beams may be provided between the two adjacent sub-compartments 111, and the multiple partition beams may be arranged at intervals along the width direction Y of the box.

[0297] Sub-compartment 111 can have various shapes, such as cylindrical or prism-shaped. Prisms can be triangular, quadrangular, pentagonal, or hexagonal. Along the length (X) of the box, sub-compartment 111 can accommodate one or multiple batteries 2; along the height (Z) of the box, sub-compartment 111 can accommodate one or multiple batteries 2; and along the width (Z) of the box, sub-compartment 111 can accommodate one or multiple batteries 2.

[0298] In this embodiment, the battery compartment 11 is divided into multiple sub-compartments 111, each of which can accommodate the first battery group 2a, so that the first battery group 2a can be more regularly accommodated in the battery compartment 11, making it easier to install the batteries 2 in the first battery group 2a.

[0299] In some embodiments, please continue to refer to Figures 12 to 14. Along the height direction Z of the box, the battery compartment 11 only accommodates one first battery group 2a, and Y1 batteries 2 in each first battery group 2a are arranged along the height direction Z of the box, 2≤Y1≤10.

[0300] Y1 can be 2, 3, 4, 5, 6, 7, 8, 9, 10.

[0301] It is understood that all batteries 2 in the first battery pack 2a are arranged along the height direction Z of the housing. In an embodiment where a sub-compartment 111 accommodates only one first battery pack 2a, it is understood that along the height direction Z of the housing, the sub-compartment 111 accommodates multiple batteries 2, each of which is connected in series. As an example, along the width direction Y of the housing, the sub-compartment 111 accommodates only one battery 2; and along the length direction X of the housing, the sub-compartment 111 accommodates only one battery 2.

[0302] As an example, along the length direction X of the box body, support members 113 are provided on both sides of each sub-compartment 111. Along the height direction Z of the box body, the support members 113 are located at the bottom of the battery 2. The support members 113 are used to support the battery 2. The support members 113 can be installed on the compartment wall and the partition 112 of the battery compartment 11. The provision of the support members 113 can, on the one hand, improve the stability of each battery 2 in the sub-compartment 111; on the other hand, it can maintain a certain distance between two adjacent batteries 2 in the height direction Z of the box body in the sub-compartment 111, so that it is not easy to affect the adjacent battery 2 when removing and installing one battery 2.

[0303] In an embodiment in which the box 1 has an electrical compartment 14 and a main control compartment 13, the main control unit in the main control compartment 13 can realize high-voltage control and communication of the first battery group 2a (battery cluster), and the bus unit in the electrical compartment 14 can realize parallel bus connection of multiple first battery groups 2a, thereby realizing safe connection between multiple first battery groups 2a and the DC side of the energy storage inverter 20.

[0304] In this embodiment, all batteries 2 in the first battery pack 2a are arranged along the height direction Z of the housing, which facilitates the series connection of all batteries 2 in the first battery pack 2a. Y1 is set between 2 and 10 to prevent Y1 from being too large. The number of batteries 2 arranged along the height direction Z of the housing within the battery compartment 11 is limited, which helps improve space utilization in the battery compartment 11.

[0305] In some embodiments, please refer to Figures 15-18. Figure 15 is an isometric view of a battery cell 21 provided in some embodiments of the present application; Figure 16 is an exploded view of the battery cell 21 shown in Figure 15; Figure 17 is a cross-sectional exploded view of the battery cell 21 shown in Figure 15 taken along the UW plane; and Figure 18 is a cross-sectional exploded view of the battery cell 21 shown in Figure 15 taken along the VW plane. Embodiments of the present application also provide a battery cell 21, comprising a housing 211 and at least one electrode assembly 213, wherein the electrode assembly 213 is housed within the housing 211. The housing 211 is in the shape of a right parallelepiped. The size of the housing 211 in the first direction U is W1, the size of the housing 211 in the second direction V is T1, and the size of the housing 211 in the third direction W is K1. One of the first direction U, the second direction V, and the third direction W is parallel to the length direction X of the box, another is parallel to the width direction Y of the box, and the third is parallel to the height direction Z of the box. The housing 211 includes a first wall 2113 and a second wall 2113 that are oppositely arranged along the first direction U. 114. The third wall 2115 and the fourth wall 2116 are arranged opposite to each other along the second direction V, and the fifth wall 2117 and the sixth wall 2118 are arranged opposite to each other along the third direction W. The sum of the thicknesses of the first wall 2113 and the second wall 2114 is a, the sum of the thicknesses of the third wall 2115 and the fourth wall 2116 is b, and the sum of the thicknesses of the fifth wall 2117 and the sixth wall 2118 is c, satisfying: (W1-a)*(T1-b)*(K1-c) / (W1*T1*K1)≥90%.

[0306] There can be one or more electrode assemblies 213 in the housing 211. If there are more than one electrode assemblies 213 in the housing 211, the multiple electrode assemblies 213 can be connected in parallel.

[0307] The housing 211 is in the shape of a right parallelepiped, which may be a rectangular parallelepiped, a cube, or the like. Of the six walls of the housing 211, four walls may form the housing 211, with the other two walls serving as end caps 2112. Alternatively, five walls may form the housing 211, with the other wall serving as end caps 2112. The dimensions of the housing 211 in the first direction U, the dimensions of the housing 211 in the second direction V, the dimensions of the housing 211 in the third direction W, the thickness of the first wall 2113, the thickness of the second wall 2114, the thickness of the third wall 2115, the thickness of the fourth wall 2116, the thickness of the fifth wall 2117, and the thickness of the sixth wall 2118 may all be measured using a vernier caliper.

[0308] As an example, the first wall 2113, the second wall 2114, the third wall 2115, the fourth wall 2116, the fifth wall 2117, and the sixth wall 2118 are all aluminum alloys. The aluminum alloy includes the following composition by mass percentage: aluminum ≥ 96.7%, 0.05% ≤ copper ≤ 0.2%, iron ≤ 0.7%, manganese ≤ 1.5%, silicon ≤ 0.6%, zinc ≤ 0.1%, other individual elements ≤ 0.05%, and other elements in total ≤ 0.15%.

[0309] As an example, the first direction U is the length direction of the outer shell 211 of the battery cell 21, the second direction V is the width direction of the outer shell 211 of the battery cell 21, and the third direction W is the height direction of the outer shell 211 of the battery cell 21. It can be understood that W1 is the length of the outer shell 211 of the battery cell 21, T1 is the width of the outer shell 211 of the battery cell 21, and K1 is the height of the outer shell 211 of the battery cell 21.

[0310] (W1-a)*(T1-b)*(K1-c) / (W1*T1*K1) can be any one of the point values ​​of 90%, 90.5%, 91%, 91.5%, 92%, 92.5%, 93%, 93.5%, 94%, 94.5%, 95%, 95.5%, 96%, 96.5%, 97%, 97.5%, 98%, 98.5%, 99%, 99.5%, etc., or a range value between any two of them.

[0311] Wherein, (W1-a)*(T1-b)*(K1-c) can be understood as the volume of the internal space of the housing 211, that is, the volume of the space enclosed by the inner surface of the housing 211. W1*T1*K1 is the volume of the housing 211.

[0312] If the outer surfaces of the six walls of the housing 211 are all planar, W1, T1, and K1 are measured based on the outer surface of each wall. For example, if the outer surface of the fifth wall 2117 and the outer surface of the sixth wall 2118 are both planar, K1 is the distance between the outer surfaces of the fifth wall 2117 and the outer surfaces of the sixth wall 2118 along the third direction W.

[0313] If a protrusion or recess is formed on the outer surface of a wall of the housing 211, W1, T1, and K1 are measured relative to the planar area of ​​that outer surface (i.e., the area excluding the protrusion or recess). For example, if the outer surface of the fifth wall 2117 is planar and the outer surface of the sixth wall 2118 is formed with a first protrusion (e.g., if the sixth wall 2118 is the end cap 2112, the protrusion formed on the end cap 2112 is the first protrusion), K1 is the distance along the third direction W between the planar area of ​​the outer surface of the sixth wall 2118 excluding the first protrusion and the outer surface of the fifth wall 2117. If the outer surface of the sixth wall 2118 is formed with a first protrusion and the outer surface of the fifth wall 2117 is formed with a second protrusion, K1 is the distance along the third direction W between the planar area of ​​the outer surface of the fifth wall 2117 excluding the second protrusion and the planar area of ​​the outer surface of the sixth wall 2118 excluding the first protrusion.

[0314] If all six walls of the housing 211 are of uniform thickness, the thickness of each wall can be determined by measuring the distance between the outer and inner surfaces of the wall from any position along the wall. If a wall of the housing 211 is of uneven thickness, the thickness of the wall can be determined by measuring the distance between the outer and inner surfaces of the wall at the point where the thickness is greatest. In other words, if the thickness of a wall is uneven, the maximum thickness of that wall is used to calculate a, b, or c.

[0315] In such a battery cell 21, the ratio of the volume of the internal space of the shell 211 of the battery cell 21 to the volume of the shell 211 is above 90%, so that the internal space of the shell 211 accounts for a relatively large proportion, and the space of the shell 211 that can be used to accommodate the electrode assembly 213 is increased. Under the same chemical system, the volume energy density of the battery cell 21 can be improved.

[0316] The following is a detailed description based on specific experimental data:

[0317] In the experiment, the battery cell 21 is a square-shell battery cell 21 . The shell 2111 of the outer shell 211 is a hollow structure with one end open. There is only one end cover 2112 in the battery cell 21 .

[0318] Table 2

[0319] According to Table 2 above, comparing Examples 10-13 with Comparative Example 2, it can be seen that when the positive electrode material of battery cell 21 includes a lithium-containing phosphate, (W1-a)*(T1-b)*(K1-c) / (W1*T1*K1) ≥ 90%, which can effectively improve the volumetric energy density of battery cell 21. Comparing Examples 14-17 with Comparative Example 3, it can be seen that when the positive electrode material of battery cell 21 includes a lithium transition metal oxide, (W1-a)*(T1-b)*(K1-c) / (W1*T1*K1) ≥ 90%, which can effectively improve the volumetric energy density of battery cell 21. Comparing Examples 18-21 with Comparative Example 4, it can be seen that when battery cell 21 is a sodium ion battery cell, (W1-a)*(T1-b)*(K1-c) / (W1*T1*K1) ≥ 90%, which can effectively improve the volumetric energy density of battery cell 21.

[0320] In some embodiments, (W1-a) / W1≥97%, (T1-b) / T1≥96.5%, and (K1-c) / K1≥96.5%.

[0321] By setting the ratio of W1-a to W1 to 97% or greater, the interior of the housing 211 is increased while the length of the battery cell 21 remains unchanged, thereby accommodating a longer electrode assembly 213. This improves the volumetric energy density of the battery cell 21 while maintaining the same chemical material system. (W1-a) / W1 can be any value, such as 97%, 97.5%, 98%, 98.5%, 99%, or 99.5%, or a range between any two values.

[0322] By setting the ratio of T1-b to T1 to above 96.5%, the width of the interior space of the housing 211 increases while the width of the battery cell 21 remains unchanged, thereby accommodating a wider electrode assembly 213. This improves the volumetric energy density of the battery cell 21 while maintaining the same chemical material system. (T1-b) / T1 can be any value among 96.5%, 97%, 97.5%, 98%, 98.5%, 99%, 99.5%, or any range therebetween.

[0323] By setting the ratio of K1-c to K1 to above 96.5%, the height of the interior space of the housing 211 is increased while the height of the battery cell 21 remains unchanged, thereby accommodating a taller electrode assembly 213. This also increases the volumetric energy density of the battery cell 21 while maintaining the same chemical material system. (K1-c) / K1 can be any value among 96.5%, 97%, 97.5%, 98%, 98.5%, 99%, 99.5%, or any range therebetween.

[0324] In some embodiments, please continue to refer to Figures 15-18, the outer shell 211 includes a shell body 2111 and an end cover 2112, the shell body 2111 has an opening, and the end cover 2112 covers the opening; the shell body 2111 includes an integrally formed first wall 2113, a second wall 2114, a third wall 2115, a fourth wall 2116 and a fifth wall 2117, and the end cover 2112 is the sixth wall 2118.

[0325] In this embodiment, the housing 2111 is a hollow structure with an opening at one end, and the housing 211 includes a single end cap 2112. The end cap 2112 is separately provided and connected to the housing 2111, and the end cap 2112 and the housing 2111 can be welded or crimped.

[0326] When assembling the battery 2, the electrode terminal 212 can be first installed on the end cover 2112, and then the electrode assembly 213 can be accommodated in the shell 2111, and then the end cover 2112 can be covered on the opening of the shell 2111. This can reduce the difficulty of installing the electrode assembly 213 in the shell 211 and reduce the difficulty of installing the electrode terminal 212 in the shell 211.

[0327] In some embodiments, please continue to refer to Figures 17 and 18. The thickness of the first wall 2113 and the second wall 2114 are both a1, 2*a1=a; the thickness of the third wall 2115 and the fourth wall 2116 are both b1, 2*b1=b; the thickness of the fifth wall 2117 is c1, and the thickness of the sixth wall 2118 is c2, c2>c1, c1>a1, c1>b1. 0.5mm≤a1≤1.5mm, 0.5≤b1≤1.5mm, 1.0mm≤c1≤2.5mm, 1.5mm≤c2≤4mm.

[0328] In order to reduce the possibility of interference between the electrode assembly 213 and the shell 2111 during the process of being installed into the shell 2111 and reduce the risk of damage to the electrode assembly 213, a certain assembly gap (i.e., shell entry gap) will be reserved for the electrode assembly 213 when designing the shell 2111. The assembly gap can be 0.8-2mm.

[0329] In addition, in order to reduce the possibility of internal short circuit of the battery cell 21, an insulating member can be provided inside the shell 211, but the insulating member will inevitably occupy a portion of the internal space of the shell 211, thereby reducing the space left for the electrode assembly 213 and the electrolyte.

[0330] In some embodiments, the battery cell 21 may further include a first insulating member 214 and a second insulating member 215, the first insulating member 214 being arranged between the fifth wall 2117 and the electrode assembly 213, and abutting against the fifth wall 2117; the second insulating member 215 being arranged between the sixth wall 2118 and the electrode assembly 213, and abutting against the sixth wall 2118; the maximum dimension of the first insulating member 214 in the third direction W is e1, and the maximum dimension of the second insulating member 215 in the third direction W is e2, satisfying: (W1-a-1.6mm)*(T1-b-1.6mm)*(K1-c-e1-e2) / (W1*T1*K1)≥88%, 0.3mm≤e1≤1.2mm, and 2mm≤e2≤10mm.

[0331] (W1-a-1.6mm)*(T1-b-1.6mm)*(K1-c-e1-e2) / (W1*T1*K1) can be any one of the point values ​​88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, etc., or a range value between any two of them.

[0332] e1 can be any point value among 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, etc., or a range value between any two of them.

[0333] e2 can be any point value of 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, etc., or a range value between any two of them.

[0334] In this embodiment, W1-a-1.6mm indicates the maximum dimension of the internal space of the outer shell 211 reserved for the electrode assembly 213 along the first direction U, when the assembly clearance between the electrode assembly 213 and the shell 2111 is 0.8mm. T1-b-1.6mm indicates the maximum dimension of the internal space of the outer shell 211 reserved for the electrode assembly 213 along the second direction V, when the assembly clearance between the electrode assembly 213 and the shell 2111 is 0.8mm. K1-c-e1-e2 indicate the maximum dimension of the internal space of the outer shell 211 reserved for the electrode assembly 213 along the third direction W, when a first insulating member 214 is disposed between the fifth wall 2117 and the electrode assembly 213, abutting the fifth wall 2117, and a second insulating member 215 is disposed between the sixth wall 2118 and the electrode assembly 213, abutting the sixth wall 2118. The first insulating member 214 can be a bottom support plate, and the second insulating member 215 can be lower plastic.

[0335] In this embodiment, (W1-a-1.6mm)*(T1-b-1.6mm)*(K1-c-e1-e2) / (W1*T1*K1)≥88%, so that the space reserved for the electrode assembly 213 inside the shell 211 is increased, allowing it to accommodate a larger electrode assembly 213, so that the volume energy density of the battery cell 21 is further improved.

[0336] In some embodiments, the battery cell 21 may further include a first insulating member 214 and a second insulating member 215, the first insulating member 214 is arranged between the fifth wall 2117 and the electrode assembly 213, and abuts against the fifth wall 2117; the second insulating member 215 is arranged between the sixth wall 2118 and the electrode assembly 213, and abuts against the sixth wall 2118; the maximum dimension of the first insulating member 214 in the third direction W is e1, and the maximum dimension of the second insulating member 215 in the third direction W is e2, satisfying: (W1-a-4mm)*(T1-b-4mm)*(K1-c-e1-e2) / (W1*T1*K1)≥85%, 0.3mm≤e1≤1.2mm, and 2mm≤e2≤10mm.

[0337] (W1-a-4mm)*(T1-b-4mm)*(K1-c-e1-e2) / (W1*T1*K1) can be any one of the point values ​​of 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, etc., or a range value between any two of them.

[0338] e1 can be any point value among 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, etc., or a range value between any two of them.

[0339] e2 can be any point value of 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, etc., or a range value between any two of them.

[0340] In this embodiment, W1-a-4mm indicates the maximum dimension of the internal space of the outer shell 211 reserved for the electrode assembly 213 along the first direction U, when the assembly gap between the electrode assembly 213 and the shell 2111 is 2mm. T1-b-4mm indicates the maximum dimension of the internal space of the outer shell 211 reserved for the electrode assembly 213 along the second direction V, when the assembly gap between the electrode assembly 213 and the shell 2111 is 2mm. K1-c-e1-e2 indicates the maximum dimension of the internal space of the outer shell 211 reserved for the electrode assembly 213 along the third direction W, when a first insulating member 214 is disposed between the fifth wall 2117 and the electrode assembly 213, abutting the fifth wall 2117, and a second insulating member 215 is disposed between the sixth wall 2118 and the electrode assembly 213, abutting the sixth wall 2118.

[0341] In this embodiment, (W1-a-4mm)*(T1-b-4mm)*(K1-c-e1-e2) / (W1*T1*K1)≥85%, so that the space reserved for the electrode assembly 213 inside the shell 211 is increased, allowing it to accommodate a larger electrode assembly 213, so that the volume energy density of the battery cell 21 is further improved.

[0342] In some embodiments, W1 ≥ T1, the first direction U is parallel to the length direction X of the box, the second direction V is parallel to the width direction Y of the box, and the third direction W is parallel to the height direction Z of the box.

[0343] As an example, the first direction U is the length direction of the shell 211 of the battery cell 21, the second direction V is the width direction of the shell 211 of the battery cell 21, and the third direction W is the height direction of the shell 211 of the battery cell 21, so that the length direction of the shell 211 is parallel to the length direction X of the box body, the width direction of the shell 211 is parallel to the width direction Y of the box body, and the height direction of the shell 211 is parallel to the height direction Z of the box body.

[0344] When the end cover 2112 is set at only one end of the shell 2111 and W1≥T1, the end cover 2112 and the fifth wall 2117 of the shell 211 are relatively set along the height direction Z of the box body, the first wall 2113 and the second wall 2114 of the shell 211 are relatively set along the length direction X of the box body, and the third wall 2115 and the fourth wall 2116 of the shell 211 are relatively set along the width direction Y of the box body, which is beneficial to increase the volume share of all battery cells 21 in the battery compartment 11.

[0345] In some embodiments, please refer to Figures 19-22. Figure 19 is an isometric view of a battery cell 21 provided in other embodiments of the present application; Figure 20 is an exploded view of the battery cell 21 shown in Figure 19; Figure 21 is an exploded view of the battery cell 21 shown in Figure 19 taken along the UW plane; and Figure 22 is an exploded view of the battery cell 21 shown in Figure 19 taken along the VW plane. The housing 211 includes a shell 2111 and two end caps 2112. The shell 2111 has two openings arranged opposite each other along a third direction W, and the two end caps 2112 respectively cover the two openings. The shell 2111 includes a first wall 2113, a second wall 2114, a third wall 2115, and a fourth wall 2116, which are integrally formed. The two end caps 2112 are respectively a fifth wall 2117 and a sixth wall 2118.

[0346] In this embodiment, the shell 2111 is a hollow structure with openings formed at both ends. There are two end covers 2112 in the outer shell 211 , and the two end covers 2112 respectively close the openings at both ends of the shell 2111 .

[0347] In some embodiments, please continue to refer to Figures 21 and 22. The thickness of the first wall 2113 and the thickness of the second wall 2114 are both a1, 2*a1=a; the thickness of the third wall 2115 and the thickness of the fourth wall 2116 are both b1, 2*b1=b; the thickness of the fifth wall 2117 and the thickness of the sixth wall 2118 are c1, 2*c1=c, c1>a1, c1>b1. 0.5mm≤a1≤1.5mm, 0.5≤b1≤1.5mm, 1.0mm≤c1≤4mm.

[0348] In order to reduce the possibility of interference between the electrode assembly 213 and the shell 2111 during the process of being installed into the shell 2111 and reduce the risk of damage to the electrode assembly 213, a certain assembly gap (i.e., shell entry gap) will be reserved for the electrode assembly 213 when designing the shell 2111. The assembly gap can be 0.8-2mm.

[0349] In addition, in order to reduce the possibility of internal short circuit of the battery cell 21, an insulating member can be provided inside the shell 211, but the insulating member will inevitably occupy a portion of the internal space of the shell 211, thereby reducing the space left for the electrode assembly 213 and the electrolyte.

[0350] In some embodiments, the battery cell 21 may further include a third insulating member 216 and a fourth insulating member 217, wherein the third insulating member 216 is disposed between the fifth wall 2117 and the electrode assembly 213 and abuts against the fifth wall 2117; the fourth insulating member 217 is disposed between the sixth wall 2118 and the electrode assembly 213 and abuts against the sixth wall 2118; the maximum dimension of the third insulating member 216 in the third direction W is e3, and the maximum dimension of the fourth insulating member 217 in the third direction W is e4, satisfying: (W1-a-1.6mm)*(T1-b-1.6mm)*(K1-c-e3-e4) / (W1*T1*K1)≥88%, 2mm≤e3≤10mm, and 2mm≤e4≤10mm.

[0351] (W1-a-1.6mm)*(T1-b-1.6mm)*(K1-c-e3-e4) / (W1*T1*K1) can be any one of the point values ​​88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, etc., or a range value between any two of them.

[0352] e3 can be any point value of 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, etc., or a range value between any two of them.

[0353] e4 can be any point value of 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, etc., or a range value between any two of them.

[0354] In this embodiment, W1-a-1.6mm indicates the maximum dimension of the internal space of the outer shell 211 reserved for the electrode assembly 213 along the first direction U, when the assembly gap between the electrode assembly 213 and the shell 2111 is 0.8mm. T1-b-1.6mm indicates the maximum dimension of the internal space of the outer shell 211 reserved for the electrode assembly 213 along the second direction V, when the assembly gap between the electrode assembly 213 and the shell 2111 is 0.8mm. K1-c-e3-e4 indicate the maximum dimension of the internal space of the outer shell 211 reserved for the electrode assembly 213 along the third direction W, when a third insulating member 216 is disposed between the fifth wall 2117 and the electrode assembly 213, abutting the fifth wall 2117, and a fourth insulating member 217 is disposed between the sixth wall 2118 and the electrode assembly 213, abutting the sixth wall 2118. Both the third insulating member 216 and the fourth insulating member 217 may be lower plastic.

[0355] In this embodiment, W1-a-1.6mm)*(T1-b-1.6mm)*(K1-c-e3-e4) / (W1*T1*K1)≥88%, so that the space reserved for the electrode assembly 213 inside the shell 211 is increased, allowing it to accommodate a larger electrode assembly 213, so that the volume energy density of the battery cell 21 is further improved.

[0356] In some embodiments, the battery cell 21 may further include a third insulating member 216 and a fourth insulating member 217. The third insulating member 216 is arranged between the fifth wall 2117 and the electrode assembly 213, and abuts against the fifth wall 2117; the fourth insulating member 217 is arranged between the sixth wall 2118 and the electrode assembly 213, and abuts against the sixth wall 2118; the maximum dimension of the third insulating member 216 in the third direction W is e3, and the maximum dimension of the fourth insulating member 217 in the third direction W is e4, satisfying: (W1-a-4mm)*(T1-b-4mm)*(K1-c-e3-e4) / (W1*T1*K1)≥85%, 2mm≤e3≤10mm, and 2mm≤e4≤10mm.

[0357] (W1-a-4mm)*(T1-b-4mm)*(K1-c-e3-e4) / (W1*T1*K1) can be any one of the point values ​​of 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, etc., or a range value between any two of them.

[0358] e3 can be any point value of 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, etc., or a range value between any two of them.

[0359] e4 can be any point value of 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, etc., or a range value between any two of them.

[0360] In this embodiment, W1-a-4mm indicates the maximum dimension of the internal space of the outer shell 211 reserved for the electrode assembly 213 along the first direction U, when the assembly gap between the electrode assembly 213 and the shell 2111 is 2mm. T1-b-4mm indicates the maximum dimension of the internal space of the outer shell 211 reserved for the electrode assembly 213 along the second direction V, when the assembly gap between the electrode assembly 213 and the shell 2111 is 2mm. K1-c-e3-e4 indicates the maximum dimension of the internal space of the outer shell 211 reserved for the electrode assembly 213 along the third direction W, when a third insulating member 216 is disposed between the fifth wall 2117 and the electrode assembly 213, abutting the fifth wall 2117, and a fourth insulating member 217 is disposed between the sixth wall 2118 and the electrode assembly 213, abutting the sixth wall 2118.

[0361] In this embodiment, (W1-a-4mm)*(T1-b-4mm)*(K1-c-e3-e4) / (W1*T1*K1)≥85%, so that the space reserved for the electrode assembly 213 inside the shell 211 is increased, allowing it to accommodate a larger electrode assembly 213, so that the volume energy density of the battery cell 21 is further improved.

[0362] In some embodiments, W1 ≥ T1, the first direction U is parallel to the height direction Z of the box, the second direction V is parallel to the width direction Y of the box, and the third direction W is parallel to the length direction X of the box.

[0363] As an example, the first direction U is the length direction of the shell 211 of the battery cell 21, the second direction V is the width direction of the shell 211 of the battery cell 21, and the third direction W is the height direction of the shell 211 of the battery cell 21, so that the length direction of the shell 211 is parallel to the height direction Z of the box, the width direction of the shell 211 is parallel to the width direction Y of the box, and the height direction of the shell 211 is parallel to the length direction X of the box.

[0364] When end covers 2112 are provided at both ends of the shell 2111 and W1 ≥ T1, the two end covers 2112 of the shell 211 are arranged along the length direction X of the box body, the first wall 2113 and the second wall 2114 of the shell 211 are arranged along the height direction Z of the box body, and the third wall 2115 and the fourth wall 2116 of the shell 211 are relatively arranged along the width direction Y of the box body, which is beneficial to increase the volume share of all battery cells 21 in the battery compartment 11.

[0365] In some embodiments, 3000 cm 3 ≤W1*T1*K1≤40000cm 3 .

[0366] W1*T1*K1 can be 3000cm 3 , 5000cm 3 , 8000cm 3 , 10000cm 3 , 13000cm 3 , 15000cm 3 , 18000cm 3 , 20000cm 3 , 23000cm 3 , 25000cm 3 , 28000cm 3 30000cm 3 、33000cm 3 、35000cm 3 、38000cm 3 40000cm 3 Any point value of the above or any range of values ​​between them.

[0367] In this embodiment, W1*T1*K1≥3000cm 3 , so that the wall thickness of the shell 211 is not too small while the ratio of the volume of the internal space of the shell 211 to the volume of the shell 211 is above 90%, thereby meeting the structural strength requirements of the shell 211; W1*T1*K1≤40000cm 3 , the capacity and current of the battery cell 21 can be controlled within a suitable range, reducing the risk of damage to overcurrent components in the circuit.

[0368] In some embodiments, 3200 cm 3 ≤W1*T1*K1≤32000cm 3 .

[0369] In this embodiment, W1*T1*K1 can be 3200cm 3 3500cm 3 4200cm 3 , 5000cm 3 , 6000cm 3 7000cm 3 , 8000cm 3 , 9000cm 3 , 10000cm 3 , 11000cm 3 , 12000cm 3 , 13000cm 3 , 14000cm 3 , 15000cm 3 , 16000cm3 , 17000cm 3 , 18000cm 3 , 19000cm 3 , 20000cm 3 , 21000cm 3 , 22000cm 3 , 23000cm 3 , 24000cm 3 , 25000cm 3 , 26000cm 3 , 27000cm 3 , 28000cm 3 , 29000cm 3 30000cm 3 、31000cm 3 、32000cm 3 Any point value of the above or any range of values ​​between them.

[0370] In this embodiment, 3200 cm 3 ≤W1*T1*K1≤32000cm 3 , taking into account the structural strength of the shell 211 and the heat generation requirements of the battery cell 21, further improving the structural strength of the shell 211, and reducing the risk of damage to overcurrent components in the circuit.

[0371] In some embodiments, 3720 cm 3 ≤W1*T1*K1≤12500cm 3 .

[0372] In this embodiment, W1*T1*K1 can be 3720cm 3 3900cm 3 4200cm 3 4600cm 3 4800cm 3 , 5000cm 3 5200cm 3 , 5800cm 3 , 6000cm 3 , 6200cm 3 , 6800cm 3 7000cm 3 , 7200cm 3 , 7800cm 3 , 8000cm 3 , 8200cm 3 , 8800cm 3 , 9000cm 3, 9200cm 3 , 9800cm 3 , 10000cm 3 、10200cm 3 、10800cm 3 , 11000cm 3 11200cm 3 、11800cm 3 , 12000cm 3 、12500cm 3 Any point value of the above or any range of values ​​between them.

[0373] In some embodiments, 4000 cm 3 ≤W1*T1*K1≤6000cm 3 .

[0374] In this embodiment, it can be 4000cm 3 4100cm 3 4200cm 3 4300cm 3 4400cm 3 4500cm 3 4600cm 3 4700cm 3 4800cm 3 4900cm 3 , 5000cm 3 5100cm 3 5200cm 3 5300cm 3 5400cm 3 5500cm 3 5600cm 3 5700cm 3 , 5800cm 3 , 5900cm 3 , 6000cm 3 Any point value of the above or any range of values ​​between them.

[0375] In some embodiments, the positive electrode material of the battery cell 21 includes lithium-containing phosphate, which satisfies the following conditions: C≥350 Ah, C / ((W1-a)*(T1-b)*(K1-c))≥118 Ah / L.

[0376] When the positive electrode material of the battery cell 21 includes lithium phosphate and C≥350Ah, setting C / ((W1-a)*(T1-b)*(K1-c)) to above 118Ah / L can increase the volume ratio of the internal space of the outer shell 211 of the battery cell 21, which is conducive to achieving a ratio of the volume of the internal space of the outer shell 211 of the battery cell 21 to the volume of the outer shell 211 of above 90%.

[0377] In some embodiments, the positive electrode material of the battery cell 21 includes a lithium transition metal oxide, which satisfies the following conditions: C≥650 Ah, C / ((W1-a)*(T1-b)*(K1-c))≥190 Ah / L.

[0378] When the positive electrode material of the battery cell 21 includes lithium transition metal oxide and C≥650Ah, setting C / ((W1-a)*(T1-b)*(K1-c)) to above 190Ah / L can increase the volume ratio of the internal space of the outer shell 211 of the battery cell 21, which is conducive to achieving a ratio of the volume of the internal space of the outer shell 211 of the battery cell 21 to the volume of the outer shell 211 of more than 90%.

[0379] In some embodiments, the battery cell 21 is a sodium ion battery cell, which satisfies the following conditions: C≥260Ah, C / ((W1-a)*(T1-b)*(K1-c))≥87Ah / L.

[0380] When the battery cell 21 is a sodium ion battery cell and C ≥ 260Ah, setting C / ((W1-a)*(T1-b)*(K1-c)) to above 87Ah / L can increase the volume ratio of the internal space of the outer shell 211 of the battery cell 21, which is conducive to achieving a ratio of the volume of the internal space of the outer shell 211 of the battery cell 21 to the volume of the outer shell 211 of above 90%.

[0381] In addition, an embodiment of the present application provides an energy storage system 100, including an energy storage converter 20 and the energy storage device 10 provided by any one of the M above embodiments, where the energy storage device 10 is electrically connected to the energy storage converter 20.

[0382] Wherein, M is a positive integer, and M can be 1, 2, 3, 4, 5, 6, 7, 8, etc.

[0383] In some embodiments, M=2, A=2; or, M=4, A=4; or, M=8, A=8.

[0384] In addition, an embodiment of the present application further provides an energy storage device 10, which is used to electrically connect an energy storage converter 20. The energy storage converter 20 can be used in conjunction with M energy storage devices 10, where M is a positive integer, the rated output power of the energy storage converter 20 is P, in W, the energy of the energy storage device 10 is Q, in Wh, and the time it takes for the energy storage device 10 to discharge from a fully charged state to a fully discharged state is A, in h. The energy storage device 10 includes a housing 1 and a plurality of batteries 2, the housing 1 includes a battery compartment 11, and the plurality of batteries 2 are accommodated in the battery compartment 11. The battery 2 includes a housing 1 and a plurality of battery cells 21 accommodated in the housing 1. The capacity of the battery cell 21 is C, in Ah, and the platform voltage of the battery cell 21 is U0, in V. The battery compartment 11 houses N1 batteries 2, each consisting of X1 first battery packs 2a connected in parallel. Each first battery pack 2a consists of Y1 batteries 2 connected in series, where N1 = X1 * Y1. The battery 2 includes N2 battery cells 21, each consisting of Y2 second battery packs 21b connected in series. Each second battery pack 21b consists of X2 battery cells 21 connected in parallel, where N2 = X2 * Y2, and Q = N1 * N2 * C * U0. The maximum operating voltage of the DC side of the energy storage converter 20 is U1, and the minimum operating voltage of the DC side of the energy storage converter 20 is U2, where U2 < U0 * Y1 * Y2 < U1.

[0385] Among them, the positive electrode material of the battery cell 21 includes lithium iron phosphate, P=4900000W, M=A=4, U1=1500V, U2=900V, C=530Ah, U0=3.23, X1=4, Y1=8, X2=2, Y2=52, P / (M*Q / A)=P / (M*X1*Y1*X2*Y2*C*U0 / A)=0.86.

[0386] It should be noted that, unless there is any conflict, the embodiments and features in the embodiments of this application can be combined with each other.

[0387] The above embodiments are intended only to illustrate the technical solutions of this application and are not intended to limit this application. Those skilled in the art will appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this application are intended to be within the scope of protection of this application.

Claims

1. An energy storage device, used for electrically connecting an energy storage converter, wherein: The energy storage device comprises a box and at least one battery, the box comprises a battery compartment, the battery compartment contains N1 batteries, the N1 batteries are formed by X1 first battery groups connected in parallel, each of the first battery groups is formed by Y1 batteries connected in series; or, the N1 batteries are formed by Y1 second battery groups connected in series, each of the second battery groups is formed by X1 batteries connected in parallel, satisfying: N1≥1, X1≥1, Y1≥1, N1=X1*Y1; the battery comprises N2 battery cells, the N2 battery cells are formed by X2 first battery cell groups connected in parallel Each of the first battery monomer groups is formed by Y2 battery monomers connected in series; or, N2 battery monomers are formed by Y2 second battery monomer groups connected in series, and each of the second battery monomer groups is formed by X2 battery monomers connected in parallel, satisfying: N2≥1, X2≥1, Y2≥1, N2=X2*Y2; the capacity of the battery monomer is C, in Ah, the platform voltage of the battery monomer is U0, in V, the total number of the battery monomers in the battery compartment is N, the energy of the energy storage device is Q, in Wh, Q=N*C*U0, N=N1*N2; The energy storage inverter can be used to cooperate with M energy storage devices, where M is a positive integer, the rated output power of the energy storage inverter is P, in W, the time for the energy storage device to discharge from a fully charged state to a fully discharged state is A, in h, the maximum operating voltage of the DC side of the energy storage inverter is U1, and the minimum operating voltage of the DC side of the energy storage inverter is U2, satisfying: 0.7≤P / (M*Q / A)≤0.99, U2<U0*Y1*Y2<U1.

2. The energy storage device according to claim 1, wherein: 0.75≤P / (M*Q / A)≤0.95; optionally, 0.85≤P / (M*Q / A)≤0.

93.

3. The energy storage device according to claim 1 or 2, wherein: The positive electrode material of the battery cell includes lithium-containing phosphate, 2.8V≤U0≤3.6V, 250≤Y1*Y2≤468.

4. The energy storage device according to claim 3, wherein: The positive electrode material of the battery cell includes lithium iron phosphate, 3.1V≤U0≤3.3V, 400≤Y1*Y2≤424.

5. The energy storage device according to claim 3 or 4, wherein: 3.5*10 6 W≤P≤7.5*10 6 W,M=A,1≤X1*X2≤18。 6. The energy storage device according to claim 5, wherein: X1＝1。 7. The energy storage device according to claim 6, wherein: X2=1, 2000Ah≤C≤11000Ah.

8. The energy storage device according to claim 7, wherein: 2500Ah≤C≤6000Ah.

9. The energy storage device according to claim 6, wherein: X2=2,1000Ah≤C≤5500Ah.

10. The energy storage device according to claim 9, wherein: 2000Ah≤C≤4000Ah.

11. The energy storage device according to claim 5, wherein: 2≤X1≤6。 12. The energy storage device according to claim 11, wherein: X1=4, X2=1, 500Ah≤C≤2600Ah.

13. The energy storage device according to claim 12, wherein: 800Ah≤C≤1500Ah.

14. The energy storage device according to claim 11, wherein: X1=4, X2=2, 250Ah≤C≤1300Ah.

15. The energy storage device according to claim 14, wherein: 350Ah≤C≤1000Ah; optionally, 500Ah≤C≤700Ah.

16. The energy storage device according to any one of claims 11 to 15, wherein: X1 first battery groups are arranged along the length direction of the box.

17. The energy storage device according to claim 16, wherein: The battery compartment includes a plurality of sub-compartments, and the plurality of sub-compartments are arranged along the length direction of the box body. Along the length direction of the box body, each of the sub-compartments accommodates one of the first battery packs.

18. The energy storage device according to claim 1, wherein: The positive electrode material of the battery cell includes lithium transition metal oxide, 2.8V≤U0≤4.35V, 210≤Y1*Y2≤530.

19. The energy storage device according to claim 18, wherein: 3.5*10 6 W≤P≤7.5*10 6 W,M=A,1≤X1*X2≤18。 20. The energy storage device according to claim 19, wherein: X1＝1。 21. The energy storage device according to claim 20, wherein: X2=1, 1500Ah≤C≤13400Ah.

22. The energy storage device according to claim 21, wherein: 3000Ah≤C≤7000Ah.

23. The energy storage device according to claim 20, wherein: X2=2,750Ah≤C≤6670Ah.

24. The energy storage device according to claim 23, wherein: 1800Ah≤C≤4000Ah.

25. The energy storage device according to claim 19, wherein: 2≤X1≤6。 26. The energy storage device according to claim 25, wherein: X1=4, X2=1, 375Ah≤C≤3300Ah.

27. The energy storage device according to claim 26, wherein: 700Ah≤C≤1600Ah.

28. The energy storage device of claim 25, wherein: X1=4, X2=2, 200Ah≤C≤1600Ah.

29. The energy storage device of claim 28, wherein: 340Ah≤C≤1050Ah; optionally, 490Ah≤C≤720Ah.

30. The energy storage device according to any one of claims 25 to 29, wherein: X1 first battery groups are arranged along the length direction of the box.

31. The energy storage device of claim 30, wherein: The battery compartment includes a plurality of sub-compartments, and the plurality of sub-compartments are arranged along the length direction of the box body. Along the length direction of the box body, each of the sub-compartments accommodates one of the first battery packs.

32. The energy storage device of claim 1, wherein: The battery cell is a sodium ion battery cell, 1.5V≤U0≤4V, 230≤Y1*Y2≤1000.

33. The energy storage device of claim 32, wherein: 3.5*10 6 W≤P≤7.5*10 6 W,M=A,1≤X1*X2≤18。 34. The energy storage device of claim 33, wherein: X1＝1。 35. The energy storage device of claim 34, wherein: X2=1, 1200Ah≤C≤18000Ah.

36. The energy storage device of claim 35, wherein: 2000Ah≤C≤10000Ah.

37. The energy storage device of claim 34, wherein: X2=2, 600Ah≤C≤9000Ah.

38. The energy storage device of claim 37, wherein: 1600Ah≤C≤4000Ah.

39. The energy storage device of claim 33, wherein: 2≤X1≤6。 40. The energy storage device of claim 39, wherein: X1=4, X2=1, 300Ah≤C≤4000Ah.

41. The energy storage device of claim 40, wherein: 700Ah≤C≤1500Ah.

42. The energy storage device of claim 39, wherein: X1=4, X2=2, 150Ah≤C≤1500Ah.

43. The energy storage device of claim 42, wherein: 350Ah≤C≤1200Ah; optionally, 400Ah≤C≤650Ah.

44. The energy storage device according to any one of claims 39 to 43, wherein: X1 first battery groups are arranged along the length direction of the box.

45. The energy storage device of claim 44, wherein: The battery compartment includes a plurality of sub-compartments, and the plurality of sub-compartments are arranged along the length direction of the box body. Along the length direction of the box body, each of the sub-compartments accommodates one of the first battery packs.

46. ​​The energy storage device according to any one of claims 1 to 45, wherein: Along the height direction of the box body, the battery compartment accommodates only one first battery group, and Y1 batteries in each first battery group are arranged along the height direction of the box body, 2≤Y1≤10.

47. The energy storage device according to any one of claims 1 to 46, wherein: The battery cell comprises a housing and at least one electrode assembly, wherein the electrode assembly is accommodated in the housing; The shell is in the shape of a right parallelepiped, the size of the shell in the first direction is W1, the size of the shell in the second direction is T1, the size of the shell in the third direction is K1, one of the first direction, the second direction and the third direction is parallel to the length direction of the box, another is parallel to the width direction of the box, and the third is parallel to the height direction of the box; The shell includes a first wall and a second wall arranged opposite to each other along the first direction, a third wall and a fourth wall arranged opposite to each other along the second direction, and a fifth wall and a sixth wall arranged opposite to each other along the third direction. The sum of the thicknesses of the first wall and the second wall is a, the sum of the thicknesses of the third wall and the fourth wall is b, and the sum of the thicknesses of the fifth wall and the sixth wall is c, satisfying: (W1-a)*(T1-b)*(K1-c) / (W1*T1*K1)≥90%.

48. The energy storage device of claim 47, wherein: (W1-a) / W1≥97%, (T1-b) / T1≥96.5%, and (K1-c) / K1≥96.5%.

49. The energy storage device of claim 47 or 48, wherein: The housing comprises a shell and an end cover, the shell has an opening, and the end cover covers the opening; The shell includes the first wall, the second wall, the third wall, the fourth wall and the fifth wall which are integrally formed, and the end cover is the sixth wall.

50. The energy storage device of claim 49, wherein: The battery cell further includes a first insulating member and a second insulating member, wherein the first insulating member is disposed between the fifth wall and the electrode assembly and abuts against the fifth wall; the second insulating member is disposed between the sixth wall and the electrode assembly and abuts against the sixth wall; The maximum dimension of the first insulating part in the third direction is e1, and the maximum dimension of the second insulating part in the third direction is e2, satisfying: (W1-a-1.6mm)*(T1-b-1.6mm)*(K1-c-e1-e2) / (W1*T1*K1)≥88%, 0.3mm≤e1≤1.2mm, and 2mm≤e2≤10mm.

51. The energy storage device of claim 49 or 50, wherein: The battery cell further includes a first insulating member and a second insulating member, wherein the first insulating member is disposed between the fifth wall and the electrode assembly and abuts against the fifth wall; the second insulating member is disposed between the sixth wall and the electrode assembly and abuts against the sixth wall; The maximum dimension of the first insulating part in the third direction is e1, and the maximum dimension of the second insulating part in the third direction is e2, satisfying: (W1-a-4mm)*(T1-b-4mm)*(K1-c-e1-e2) / (W1*T1*K1)≥85%, 0.3mm≤e1≤1.2mm, and 2mm≤e2≤10mm.

52. The energy storage device according to any one of claims 49 to 51, wherein: W1≥T1, the first direction is parallel to the length direction of the box, the second direction is parallel to the width direction of the box, and the third direction is parallel to the height direction of the box.

53. The energy storage device of claim 47 or 48, wherein: The housing comprises a shell and two end covers, the shell has two openings arranged opposite to each other along the third direction, and the two end covers cover the two openings respectively; The shell includes the first wall, the second wall, the third wall and the fourth wall which are integrally formed, and the two end covers are the fifth wall and the sixth wall respectively.

54. The energy storage device of claim 53, wherein: The battery cell further includes a third insulating member and a fourth insulating member, wherein the third insulating member is disposed between the fifth wall and the electrode assembly and abuts against the fifth wall; the fourth insulating member is disposed between the sixth wall and the electrode assembly and abuts against the sixth wall; The maximum dimension of the third insulating part in the third direction is e3, and the maximum dimension of the fourth insulating part in the third direction is e4, satisfying: (W1-a-1.6mm)*(T1-b-1.6mm)*(K1-c-e3-e4) / (W1*T1*K1)≥88%, 2mm≤e3≤10mm, and 2mm≤e4≤10mm.

55. The energy storage device of claim 53 or 54, wherein: The battery cell further includes a third insulating member and a fourth insulating member, wherein the third insulating member is disposed between the fifth wall and the electrode assembly and abuts against the fifth wall; the fourth insulating member is disposed between the sixth wall and the electrode assembly and abuts against the sixth wall; The maximum dimension of the third insulating part in the third direction is e3, and the maximum dimension of the fourth insulating part in the third direction is e4, satisfying: (W1-a-4mm)*(T1-b-4mm)*(K1-c-e3-e4) / (W1*T1*K1)≥85%, 2mm≤e3≤10mm, and 2mm≤e4≤10mm.

56. The energy storage device according to any one of claims 53 to 55, wherein: W1≥T1, the first direction is parallel to the height direction of the box, the second direction is parallel to the width direction of the box, and the third direction is parallel to the length direction of the box.

57. The energy storage device according to any one of claims 47 to 56, wherein: 3000cm 3 ≤W1*T1*K1≤40000cm 3 ; Optionally, 3200cm 3 ≤W1*T1*K1≤32000cm 3 ; Optionally, 3720cm 3 ≤W1*T1*K1≤12500cm 3 ; Optionally, 4000cm 3 ≤W1*T1*K1≤6000cm 3 .

58. The energy storage device of any one of claims 47 to 57, wherein: The positive electrode material of the battery cell includes lithium-containing phosphate, which satisfies: C≥350Ah, C / ((W1-a)*(T1-b)*(K1-c))≥118Ah / L.

59. The energy storage device according to any one of claims 47 to 57, wherein: The positive electrode material of the battery cell includes a lithium transition metal oxide and satisfies: C≥650Ah, C / ((W1-a)*(T1-b)*(K1-c))≥190Ah / L.

60. The energy storage device according to any one of claims 47 to 57, wherein: The battery cell is a sodium ion battery cell, satisfying: C≥260Ah, C / ((W1-a)*(T1-b)*(K1-c))≥87Ah / L.

61. An energy storage system, wherein: include: Energy storage converter; M energy storage devices as described in any one of claims 1-60, wherein the energy storage device is electrically connected to the energy storage converter.

62. The energy storage system of claim 61, wherein: M=2, A=2; or, M=4, A=4; or, M=8, A=8.

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