Battery cell
By introducing lithium transition metal compounds and lithium phosphate layered structures into the electrode core, the problem of simultaneous thermal runaway of multiple electrode cores in large-capacity lithium-ion batteries under abuse conditions is solved, realizing active thermal runaway warning and control, and improving battery safety.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SUNGROW POWER SUPPLY CO LTD
- Filing Date
- 2026-06-10
- Publication Date
- 2026-07-10
AI Technical Summary
Under abusive conditions, multiple electrodes of a high-capacity lithium-ion battery may simultaneously reach the thermal runaway critical point, leading to heat concentration, inability to respond in time, and potentially causing serious safety accidents such as explosions and fires.
Introducing lithium transition metal compounds into the first positive electrode of the core forms a layered structure with lithium phosphate, allowing the lithium transition metal compounds to reach the thermal runaway critical point before the lithium phosphate, generating reliable voltage fluctuations and temperature anomaly signals, and constructing an active thermal runaway early warning mechanism.
It achieves effective early warning and control of thermal runaway in the core, reduces the intensity of thermal runaway, reduces the probability of explosion and fire accidents, and improves the safety performance of individual battery cells.
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Abstract
Description
Technical Field
[0001] This application relates to the field of lithium-ion battery technology, specifically to battery cells. Background Technology
[0002] With the continuous development of the lithium-ion battery energy storage industry, the capacity and size of the battery cores used in energy storage are constantly increasing, and their thermal safety issues are becoming increasingly prominent. Under abuse conditions, batteries containing multiple cores may reach the thermal runaway critical point almost simultaneously, causing a concentrated instantaneous generation of heat and gas. This makes it impossible for the battery's venting system to respond in time, ultimately leading to serious safety accidents such as explosions and fires. Summary of the Invention
[0003] In a first aspect of this application, a battery cell is provided, comprising: a housing and a first electrode core and a second electrode core housed within the housing; The first electrode core includes the first positive electrode plate. The first positive electrode plate includes: First positive current collector; A first positive electrode material layer is disposed on at least one side of a first positive electrode current collector; the first positive electrode material layer includes a first positive electrode active material and a second positive electrode active material, the first positive electrode active material includes at least a lithium transition metal compound, and the second positive electrode active material includes at least a lithium phosphate. The second electrode core includes a second positive electrode plate, and the second positive electrode plate includes: Second positive current collector; A second positive electrode material layer is disposed on at least one side of the second positive electrode current collector; the second positive electrode material layer includes a third positive electrode active material, which includes a lithium phosphate.
[0004] This application introduces a lithium transition metal compound as the first positive electrode material into the first positive electrode sheet of the electrode core. Lithium transition metal compounds have relatively low thermal stability and can preferentially reach the thermal runaway critical point in the early stages of overcharging. Lithium transition metal compounds reach the thermal runaway critical point before lithium phosphate-containing materials, and under abuse conditions (e.g., overcharging, heating, short circuits, etc.), they exhibit a preemptive heating trend compared to lithium phosphate-containing materials, forming a characteristic thermal runaway time interval. Therefore, the energy that might otherwise be concentrated in the electrode core is dispersed, which facilitates the construction of an effective thermal runaway triggering and monitoring mechanism through the battery management system. The lithium transition metal compound first generates voltage fluctuations and temperature anomalies that can be reliably identified by the battery management system. This mechanism transforms the passive response of "detecting thermal runaway only after it occurs" in traditional solutions into active control of "early warning when thermal runaway is about to occur," providing the battery management system with sufficient response time. Thus, effective early warning and control of electrode core thermal runaway are achieved.
[0005] In some embodiments, the first positive electrode material layer includes a first layer and a second layer stacked together; The first layer includes the first positive electrode active material; the second layer includes the second positive electrode active material.
[0006] In some embodiments, the mass percentage of the first positive electrode active material in the first positive electrode material layer is greater than or equal to 0.01%.
[0007] In some embodiments, the mass percentage of the first positive electrode active material in the first positive electrode material layer is r, where r satisfies:
[0008] Where C is the rated capacity of the electrode core, and A is the correction factor of the first positive electrode active material.
[0009] In some embodiments, the core satisfies at least one of the following: The range of A is 1.5-8; When the number of types of the first positive electrode active material is greater than or equal to 1
[0010] in, This represents the ratio of the mass of one type of first positive electrode active material to the sum of the masses of all first positive electrode active materials. This is a correction factor for a first positive electrode active material; The range of C is 140Ah-1500Ah.
[0011] In some embodiments, the core satisfies at least one of the following: The first positive electrode active material includes at least one of lithium nickel cobalt manganese oxide, lithium cobalt oxide, lithium nickel oxide, lithium-rich manganese-based oxide, lithium manganese oxide, and lithium manganese iron phosphate. The second positive electrode active material includes lithium iron phosphate.
[0012] In some embodiments, the sum of the areal density of the first layer and the areal density of the second layer is 360 g / m³. 2 -550g / m 2 ; In some embodiments, a first layer is disposed on at least one side of the first positive current collector, and a second layer is disposed on the side of the first layer away from the first positive current collector.
[0013] In some embodiments, the second electrode core includes a second positive electrode sheet, the second positive electrode sheet comprising: Second positive current collector; The second positive electrode material layer is disposed on at least one side of the second positive electrode current collector; the second positive electrode material layer includes a third positive electrode active material, which includes lithium phosphate.
[0014] In some embodiments, the first electrode core is close to the housing.
[0015] In some embodiments, the housing contains at least one first electrode core and at least one second electrode core.
[0016] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Detailed Implementation
[0017] The embodiments of this application are described in detail below. The embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application.
[0018] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. Furthermore, in the description of this application, unless otherwise stated, "multiple" means two or more.
[0019] The endpoints and any values of the ranges disclosed in this application are not limited to the precise ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoint values of the various ranges, the endpoint values of the various ranges and individual point values, and individual point values can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this application.
[0020] In this application, the terms "comprising" or "including" are open-ended expressions, meaning they include the content specified in this application but do not exclude other aspects.
[0021] Lithium-ion batteries are used in energy storage. Under conditions of abuse such as continuous overcharging, multiple cells are prone to thermal runaway simultaneously, causing heat and gas generation, which can lead to serious safety accidents such as explosions and fires. In this situation, the battery management system (BMS) can only passively monitor external signals such as voltage and temperature, and can only cut off the circuit after thermal runaway has occurred or even spread, making it difficult to detect and control the thermal runaway problem in a timely manner.
[0022] Therefore, in a first aspect of the embodiments of this application, this application proposes a battery cell, including a housing and a first electrode core and a second electrode core housed within the housing; The first electrode core includes: First positive electrode plate The first positive electrode includes: First positive current collector; A first positive electrode material layer is disposed on at least one side of the first positive electrode current collector; the first positive electrode material layer includes a first positive electrode active material and a second positive electrode active material, the first positive electrode active material includes at least a lithium transition metal compound, and the second positive electrode active material includes at least a lithium phosphate. The second electrode core includes a second positive electrode plate, and the second positive electrode plate includes: Second positive current collector; The second positive electrode material layer is disposed on at least one side of the second positive electrode current collector; the second positive electrode material layer includes a third positive electrode active material, which includes lithium phosphate.
[0023] By introducing a lithium transition metal compound as the first positive electrode material into the first positive electrode sheet of the core, the lithium transition metal compound, with its relatively low thermal stability, preferentially reaches the thermal runaway critical point in the early stages of overcharging. The lithium transition metal compound reaches the thermal runaway critical point before lithium phosphate-containing materials, exhibiting a preemptive heating trend under abuse conditions (e.g., overcharging, heating, short circuits), thus creating a distinct thermal runaway time interval. This disperses the energy that might otherwise be concentrated in the core, facilitating the construction of an effective thermal runaway triggering and monitoring mechanism through the battery management system. The lithium transition metal compound generates voltage fluctuations and temperature anomalies that can be reliably identified by the battery management system first. This mechanism transforms the passive response of traditional solutions, which only detects thermal runaway after it occurs, into active control, providing an early warning when thermal runaway is about to occur, thus gaining sufficient response time for the battery management system. This achieves effective early warning and control of core thermal runaway.
[0024] In the field of high-capacity lithium-ion batteries, arranging multiple electrode cores in parallel can increase the capacity of a single battery cell. However, with the continuous increase in electrode core capacity and size, the thermal safety issues of battery cells are becoming increasingly prominent. The battery cell of this application includes a first electrode core with a composite cathode material and a second electrode core made of lithium iron phosphate. The thermal runaway triggering condition of the first electrode core in the battery cell is lower than that of the second electrode core, so that multiple electrode cores in the battery cell will not experience thermal runaway simultaneously. This results in less heat accumulation and lower electrode core energy, which helps to reduce the intensity of thermal runaway and the possibility of explosions, fires, and other serious safety accidents caused by the instantaneous concentration of heat and gas generated by multiple electrode cores due to thermal runaway. As a result, it is easier to quickly detect local thermal runaway in the battery cell, and promptly introduce the battery management system to respond and cut off charging, thereby reducing the probability of serious thermal runaway accidents in the battery cell and improving the safety performance of the battery cell.
[0025] In some embodiments, the first positive electrode material layer includes a first layer and a second layer stacked together; the first layer includes the first positive electrode active material; and the second layer includes the second positive electrode active material.
[0026] This embodiment introduces a first layer containing a first positive electrode material, lithium transition metal oxide, into the first positive electrode sheet of the electrode core. The first positive electrode active material in the first layer has relatively low thermal stability and can preferentially reach the thermal runaway critical point in the early stages of overcharging. Combined with the second layer, the first layer in the electrode core reaches the thermal runaway critical point before the second layer, making the first layer exhibit a preemptive heating tendency under abuse conditions (such as overcharging, heating, short circuits, etc.) compared to the second layer, thus creating a thermal runaway condition interval between the first and second layers. Therefore, the energy that might otherwise be concentrated in the electrode core is divided into two stages, which is beneficial for constructing an effective thermal runaway trigger monitoring mechanism through the battery management system. The first layer generates voltage fluctuations and temperature anomaly signals that can be reliably identified by the battery management system first.
[0027] In some embodiments, the mass percentage of the first positive electrode active material in the first positive electrode material layer is greater than or equal to 0.01%.
[0028] By adding a first positive electrode active material, a transition metal compound, to the first layer, and ensuring that the amount of the transition metal compound accounts for more than 0.01% of the total mass of the first material layer, the transition metal compound is better able to perform its preferential response function to abuse conditions.
[0029] In some embodiments, the mass percentage of the first positive electrode active material in the first positive electrode material layer is r, where r satisfies:
[0030] Wherein, C is the rated capacity of the electrode core, and A is the correction coefficient of the first positive electrode active material.
[0031] The method for setting the mass percentage of the first positive electrode active material provided in this application, combined with correction coefficients for different first positive electrode active materials, calculates the mass percentage r of the first positive electrode active material in the first positive electrode material layer. As the mass percentage of the transition metal compound in the first positive electrode active material decreases, the timely response and early warning effects weaken, and the intensity of thermal runaway after the electrode core occurs tends to increase. As the mass percentage of the transition metal compound in the first positive electrode active material increases, the mass percentage of lithium phosphate, which serves as the second positive electrode active material, decreases, and the capacity of the electrode core tends to decrease. The value of r is related to the electrode core capacity. The calculation method of this application can balance the change in the thermal inertia of the electrode core as the rated capacity C changes, ensuring that when the first layer is preferentially triggered by thermal runaway conditions, it can generate heat controllably and appropriately. This allows the battery management system to detect anomalies in a timely manner and also reduces the likelihood of severe thermal runaway in the second positive electrode active material in the second layer due to excessively violent preferential triggering and heat accumulation in the first layer. This mechanism transforms the passive response of traditional solutions, which only detects thermal runaway after it occurs, into proactive control that provides early warning when thermal runaway is about to occur, thus giving the battery management system a sufficient response time window. This enables effective early warning and control of core thermal runaway, reducing its severity.
[0032] In some embodiments, the core satisfies at least one of the following: The range of A is 1.5-8; When the first positive electrode active material has one or more types,
[0033] in, This represents the ratio of the mass of one type of first positive electrode active material to the sum of the masses of all first positive electrode active materials. This is a correction factor for the first positive electrode active material; The range of C is 140Ah-1500Ah.
[0034] As an example, the value of A can be 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, or any value between the two.
[0035] As an example, the correction coefficient A of the first positive electrode active material is related to the thermal stability of the first positive electrode material, and can be an empirical parameter obtained by backfitting the above formula based on experimental data. The first positive electrode active material satisfying the aforementioned correction coefficient, in the first layer, has a better thermal runaway critical point separation effect in the electrode core, as set by the calculation method provided in this application. Therefore, the safety performance of the electrode core can be significantly improved.
[0036] For example, the correction factor for lithium nickel cobalt manganese oxide is 2.45, the correction factor for lithium cobalt oxide is 1.96, the correction factor for lithium nickel oxide is 1.9, the correction factor for lithium-rich manganese-based oxide is 5.4, the correction factor for lithium manganese oxide is 6.12, and the correction factor for lithium manganese iron phosphate is 7.35, etc.
[0037] When the first positive electrode active material has one or more types,
[0038] in, This represents the ratio of the mass of one type of first positive electrode active material to the sum of the masses of all first positive electrode active materials. This is a correction coefficient for one of the first positive electrode active materials. Under the aforementioned conditions, a mixture of multiple first positive electrode active materials can be used to adapt to electrode cores with different rated capacities and different BMS response mechanisms, achieving effective thermal runaway early warning. This facilitates the applicability and promotion of the electrode core of this application in different products.
[0039] The range of C is 140Ah-1500Ah. Preferably, the range of C is 140Ah-1200Ah. The rated capacity of the electrode core meets the aforementioned range. Through the design of this application, better early warning of thermal runaway can be achieved, reducing the possibility of electrode core fire and explosion, reducing the intensity of thermal runaway, and also ensuring that the electrode core can obtain a high capacity.
[0040] As an example, C represents 140Ah, 150Ah, 200Ah, 250Ah, 300Ah, 350Ah, 400Ah, 450Ah, 500Ah, 550Ah, 600Ah, 650Ah, 700Ah, 750Ah, 800Ah, 850Ah, 900Ah, 950Ah, 1000Ah, 1050Ah, 1100Ah, 1150Ah, 1200Ah, 1250Ah, 1300Ah, 1350Ah, 1400Ah, 1450Ah, 1500Ah, etc.
[0041] In some embodiments, the core satisfies at least one of the following: The first positive electrode active material includes at least one of lithium nickel cobalt manganese oxide, lithium cobalt oxide, lithium nickel oxide, lithium-rich manganese-based oxide, lithium manganese oxide, and lithium manganese iron phosphate. Compared to the second positive electrode active material containing lithium phosphate, the aforementioned first positive electrode active material has a higher energy density and lower thermal stability. When arranged in the electrode core according to the structure described in this application, it can achieve intermittent thermal runaway and reduce the intensity of thermal runaway.
[0042] The second positive electrode active material includes lithium iron phosphate. Lithium iron phosphate has relatively higher thermal stability than lithium transition metal compounds, resulting in better energy storage performance.
[0043] In some embodiments, the sum of the areal density of the first layer and the areal density of the second layer is 360 g / m³. 2 -550g / m 2 .
[0044] When the aforementioned parameter range is met, the second layer can form a relatively stable stacked structure with the first layer. The first positive electrode material layer in the electrode core has a good electrolyte wetting effect, which improves the stability of the structure and chemical properties of the first positive electrode material layer, thereby helping to improve the safety performance of the electrode core.
[0045] As an example, the sum of the areal density of the first layer and the areal density of the second layer is 360 g / m³. 2 400g / m 2 450g / m 2 500g / m 2 550g / m 2 wait.
[0046] In some embodiments, the first layer is disposed on at least one side of the first positive current collector, and the second layer is disposed on the side of the first layer away from the first positive current collector.
[0047] Setting the first layer at the junction with the first positive current collector facilitates the rapid conduction of heat generated during the release of heat and gas production in the first layer, which is then captured by the BMS. This helps to shorten the response time of the BMS and the time required to take control measures, thereby better mitigating the problem of serious safety accidents caused by thermal runaway of the electrode core.
[0048] In some embodiments, the second electrode core includes a second positive electrode sheet, the second positive electrode sheet comprising: Second positive current collector; A second positive electrode material layer is disposed on at least one side of the second positive electrode current collector; the second positive electrode material layer includes a third positive electrode active material, the third positive electrode active material including lithium phosphate.
[0049] In this embodiment of the application, in the first electrode core, the first positive electrode material layer of the first positive electrode sheet adopts a layered structure, the first positive electrode active material of the first layer is a lithium transition metal compound, and the second positive electrode active material of the second layer is a lithium phosphate. In the second electrode core, the second positive electrode material layer of the second positive electrode sheet may not be layered, and the third positive electrode active material of the second layer is a lithium phosphate.
[0050] In some embodiments, the first electrode core is close to the housing.
[0051] Meeting the aforementioned conditions facilitates the diffusion of heat generated by the exothermic gas production of the first positive electrode active material in the first electrode core through the casing. This allows the battery management system to more easily detect temperature changes within the battery cell, thereby effectively preventing large-area thermal runaway. When the second electrode core meets the aforementioned conditions and is combined with the first electrode core, the battery cell exhibits high capacity and effectively prevents thermal runaway.
[0052] In some embodiments, the housing contains at least one first electrode core and at least one second electrode core.
[0053] Multiple pole pieces can be installed inside the housing, with the total number of pole pieces being 2, 3, 4, 5, 6, 7, etc. The arrangement order of the first and second pole pieces can be designed based on actual requirements.
[0054] Alternatively, the electrode core can be a stacked core made using a lamination process or a wound core made using a winding process.
[0055] The following will explain the solution of this application with reference to embodiments. Those skilled in the art will understand that the following embodiments are for illustrative purposes only and should not be considered as limiting the scope of this application. Where specific techniques or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in the art or according to the product instructions. Reagents or instruments whose manufacturers are not specified are all conventional products that can be obtained commercially.
[0056] [Performance Testing] 1. Thermal runaway test: Test standard: Continuously charge until the battery cell reaches thermal runaway, and detect the thermal runaway occurrence time (s) and thermal runaway temperature (°C). Among them, thermal runaway time refers to the time from the application of the inducing factor to the occurrence of thermal runaway; thermal runaway temperature refers to the highest temperature during thermal runaway, that is, the peak temperature that the battery cell can reach during the thermal runaway process.
[0057] [Preparation of battery cells] Example 1 1. Preparation of the first electrode core: The rated capacity C of the first cathode core is 300 Ah. The first cathode material layer consists of two layers: a first layer and a second layer. The first cathode material of the first layer is lithium nickel cobalt manganese oxide (LiNi). 0.8 Co 0.1 Mn 0.1 O2 (NCM811); the second positive electrode active material of the second layer is lithium iron phosphate LiFePO4 (LFP). The sum of the areal densities of the first and second layers is 400 g / m³. 2 The first positive electrode active material accounts for 3.5% of the mass of the first positive electrode material layer. Specifically: (1) First positive electrode plate: The first positive electrode active material, conductive agent carbon black, and binder polyvinylidene fluoride are added to the solvent N-methylpyrrolidone to obtain the first positive electrode slurry. The first positive electrode slurry is then coated onto the surface of the first positive electrode current collector aluminum foil to form the first layer.
[0058] The second positive electrode active material, conductive agent carbon black, and binder polyvinylidene fluoride are added to the solvent N-methylpyrrolidone to obtain the second positive electrode slurry. The second positive electrode slurry is coated on the surface of the first layer to form the second layer, thus obtaining the first positive electrode sheet.
[0059] (2) Negative electrode sheet: Negative electrode active material graphite, conductive agent carbon black, binder styrene-butadiene rubber, thickener carboxymethyl cellulose are added to solvent water to obtain negative electrode slurry, and negative electrode slurry is coated on the surface of negative electrode current collector copper foil to form negative electrode sheet.
[0060] The first positive electrode, the separator (polyethylene), and the negative electrode are stacked together to form a core, which serves as the first electrode core.
[0061] 2. Preparation of the second electrode core: The third positive electrode active material of the second electrode core is lithium iron phosphate (LiFePO4) (LFP), and the rated capacity of the second electrode core is the same as that of the first electrode core. Specifically: (1) Second positive electrode sheet: The third positive electrode active material, conductive agent carbon black, and binder polyvinylidene fluoride are added to the solvent N-methylpyrrolidone to obtain the third positive electrode slurry. The third positive electrode slurry is coated on the surface of the aluminum foil of the second positive electrode current collector to form the second positive electrode material layer, thus obtaining the second positive electrode sheet.
[0062] (2) Negative electrode sheet: Negative electrode active material graphite, conductive agent carbon black, binder styrene-butadiene rubber, thickener carboxymethyl cellulose are added to solvent water to obtain negative electrode slurry, and negative electrode slurry is coated on the surface of negative electrode current collector copper foil to form negative electrode sheet.
[0063] The second positive electrode, the separator (polyethylene), and the negative electrode are stacked together to form a core, which serves as the second electrode core.
[0064] 3. Insert the first electrode core and the second electrode core into the battery casing, inject electrolyte, and assemble to form a battery cell.
[0065] Examples 2-5 The battery cell was prepared using the same method as in Example 1, except that the value of r is different in the first electrode core.
[0066] Comparative Example 1 The battery cell is assembled using two identical second electrode cores.
[0067] Table 1
[0068] Examples 6-8 The battery cell was prepared using the same method as in Example 1, except that the first positive electrode active material in the first electrode core is different.
[0069] Table 2
[0070] Note: In Example 8, “NCM811 / lithium cobalt oxide = 1:1” means that the mass ratio of NCM811 to lithium cobalt oxide is 1:1.
[0071] Examples 9-10 The battery cells were prepared using the same method as in Example 1, except that the capacitance of the first electrode core was 1200 Ah and 1500 Ah, respectively. Specifically: In Example 9, the capacitance of both the first and second electrode cores is 1200Ah; In Example 10, the capacitance of both the first and second poles is 1500Ah.
[0072] Table 3
[0073] Test results: See Table 4.
[0074] Table 4
[0075] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.
Claims
1. A battery cell, characterized in that, include: A housing and a first pole core and a second pole core housed within the housing; The first electrode core includes a first positive electrode plate. The first positive electrode includes: First positive current collector; A first positive electrode material layer is disposed on at least one side of the first positive electrode current collector; the first positive electrode material layer includes a first positive electrode active material and a second positive electrode active material, the first positive electrode active material includes at least a lithium transition metal compound, and the second positive electrode active material includes at least a lithium phosphate. The second electrode core includes a second positive electrode plate, and the second positive electrode plate includes: Second positive current collector; A second positive electrode material layer is disposed on at least one side of the second positive electrode current collector; the second positive electrode material layer includes a third positive electrode active material, the third positive electrode active material including lithium phosphate.
2. The battery cell according to claim 1, characterized in that, The first positive electrode material layer includes a first layer and a second layer stacked together; The first layer includes the first positive electrode active material; The second layer includes the second positive electrode active material.
3. The battery cell according to claim 1 or 2, characterized in that, The mass percentage of the first positive electrode active material in the first positive electrode material layer is greater than or equal to 0.01%.
4. The battery cell according to claim 1 or 2, characterized in that, The mass percentage of the first positive electrode active material in the first positive electrode material layer is r, and r satisfies: Wherein, C is the rated capacity of the electrode core, and A is the correction coefficient of the first positive electrode active material.
5. The battery cell according to claim 4, characterized in that, Meet at least one of the following: The range of A is 1.5-8; When the first positive electrode active material has one or more types, in, This represents the ratio of the mass of one type of first positive electrode active material to the sum of the masses of all first positive electrode active materials. This is a correction factor for the first positive electrode active material; The range of C is 140Ah-1500Ah.
6. The battery cell according to claim 1 or 2, characterized in that, Meet at least one of the following: The first positive electrode active material includes at least one of lithium nickel cobalt manganese oxide, lithium cobalt oxide, lithium nickel oxide, lithium-rich manganese-based oxide, lithium manganese oxide, and lithium manganese iron phosphate. The second positive electrode active material includes lithium iron phosphate.
7. The battery cell according to claim 2, characterized in that, The sum of the areal density of the first layer and the areal density of the second layer is 360 g / m³. 2 -550g / m 2 .
8. The battery cell according to claim 2, characterized in that, The first layer is disposed on at least one side of the first positive current collector, and the second layer is disposed on the side of the first layer away from the first positive current collector.
9. The battery cell according to claim 1 or 2, characterized in that, The first electrode core is close to the housing.
10. The battery cell according to claim 1 or 2, characterized in that, The housing contains at least one first electrode core and at least one second electrode core.