Battery and battery system

Abstract

The utility model provides a battery which comprises a core body provided with a positive pole piece, a negative pole piece and a diaphragm arranged between the positive pole piece and the negative pole piece, the shell can be used for accommodating the core body and comprises a top cover arranged at the top of the shell; the positive pole can be electrically connected with the positive pole piece and is arranged on the top cover; the negative pole can be electrically connected with the negative pole piece and is arranged on the top cover; the heat exchange plate is arranged in the shell, the heat exchange plate comprises a refrigeration sheet and a cooling sheet which are oppositely arranged, the refrigeration sheet and the core body are oppositely arranged so as to absorb heat emitted by the core body, and the cooling sheet and the shell are oppositely arranged so as to discharge the absorbed heat out of the shell. The heat exchange plate made of the thermoelectric material is adopted in the battery, so that the refrigeration rate of the battery is high, the requirement of large heat dissipating capacity in a short time can be met, the battery is rapidly cooled, and thermal runaway is prevented.

Description

Technical Field

[0001] This application relates to the technical field of lithium-ion batteries, and in particular, to a battery and a battery system. Background Art

[0002] As a power source for electric vehicles, lithium-ion power batteries have extremely large capacities and output powers. Under the current form requirements of continuously increasing demands for the charging speed and acceleration performance of electric vehicles, the charge and discharge rate of power batteries needs to be further increased. The increase in charge and discharge current will inevitably lead to an increase in the heat generated by the battery cells. However, as a power battery for electric vehicles, it needs to work in a suitable temperature environment. Excessive temperature will cause the side reactions inside the battery to intensify, and even problems such as the decomposition of the SEI film inside the battery. Therefore, if the heat inside the battery cannot be dissipated in time, the temperature of the battery will rise rapidly, and the excessive temperature will further lead to a decrease in the cycle life of the battery, serious decline in electrochemical performance, and even safety problems such as thermal runaway of the battery.

[0003] Currently, most conventional battery cooling systems cool the battery by using convective air or liquid outside the battery housing, so that the heat of the battery slowly spreads from the electrochemical reaction interface inside the battery to the battery housing, and then the heat is taken away by contacting the housing through the cooling system outside the battery. However, the current cooling method of such conventional batteries requires a long cooling time, low cooling efficiency, and is prone to uneven cooling of each battery cell in the battery system, and the cooling effect uniformity of each battery cell is poor. Utility Model Content

[0004] To solve the technical problem of poor cooling effect of battery cells in the existing power battery system, the present utility model provides a battery, including: a core body, provided with a positive electrode plate, a negative electrode plate, and a separator disposed between the positive electrode plate and the negative electrode plate; a housing, which can be used to accommodate the core body, including a top cover disposed on the top of the housing; a positive electrode post, which can be electrically connected to the positive electrode plate and is disposed on the top cover; a negative electrode post, which can be electrically connected to the negative electrode plate and is disposed on the top cover; a heat exchange plate, placed inside the housing, the heat exchange plate includes a refrigeration sheet and a heat dissipation sheet disposed opposite to each other, the refrigeration sheet is disposed opposite to the core body to absorb the heat dissipated by the core body, and the heat dissipation sheet is disposed opposite to the housing to discharge the absorbed heat outside the housing.

[0005] Further, the heat exchange plate is made of a thermoelectric material.

[0006] Further, a thermoelectric semiconductor is disposed between the refrigeration sheet and the heat conduction sheet.

[0007] Further, two heat exchange plates are provided.

[0008] Further, the battery further includes a heat exchange pole column disposed on the top cover, and the heat exchange plate is electrically connected to the heat exchange pole column.

[0009] Further, the heat exchange pole column includes a heat exchange positive pole column and a heat exchange negative pole column.

[0010] Further, one end of the heat exchange plate is electrically connected to the heat exchange positive pole column, and the other end of the heat exchange plate is electrically connected to the heat exchange negative pole column.

[0011] The present utility model further provides a battery system, including a plurality of batteries, an external power source and a control switch, and the control switch can control the disconnection and connection of the heat exchange plate and the external power source.

[0012] Further, a plurality of control switches are provided, and each control switch can independently control the disconnection and connection of the heat exchange pole column in the corresponding battery and the external power source.

[0013] Further, the control switch can simultaneously control the connection and disconnection of the heat exchange plates in a plurality of batteries in the battery system and the external power source.

[0014] In the battery of this embodiment, a heat exchange plate made of a thermoelectric material is adopted inside. The battery has a fast cooling rate, can meet the demand for large heat dissipation in a short time, realizes rapid cooling of the battery, and prevents the occurrence of thermal runaway. When the battery in this embodiment is used in a battery system, it can be used in cooperation with a liquid cooling system outside the battery to realize rapid and persistent heat dissipation under extreme working conditions of the battery, delay the occurrence of thermal runaway, and extend the safe operation time of the battery. Description of the Drawings

[0015] Figure 1 It is an external schematic diagram of the battery according to Embodiment 1 of the present utility model;

[0016] Figure 2 It is an internal schematic diagram of the battery according to Embodiment 1 of the present utility model;

[0017] Figure 3 It is a schematic diagram of the heat exchange plate in the battery according to Embodiment 1 of the present utility model;

[0018] Figure 4 is Figure 3 a schematic diagram of the Peltier element in the heat exchange plate in;

[0019] Figure 5 is Figure 4 a working principle diagram of the Peltier element in;

[0020] Figure 6 It is a schematic diagram of the battery system composed of the battery according to Embodiment 1 of the present utility model;

[0021] Figure 7External schematic diagram of the battery according to the second embodiment of the present utility model;

[0022] Figure 8 Internal schematic diagram of the battery according to the second embodiment of the present utility model;

[0023] Figure 9 Schematic diagram of a battery system composed of the batteries according to the second embodiment of the present utility model. Detailed implementation manners

[0024] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model. Embodiment

[0025] This embodiment provides a battery 10, which includes a housing 105 and a core 107 disposed inside the housing. The core 107 includes a battery positive electrode sheet, a battery negative electrode sheet, and a separator disposed between the battery positive electrode sheet and the battery negative electrode sheet. The electrolyte is located inside the core 107. The housing 105 is made of aluminum and is configured to be generally rectangular parallelepiped-shaped. An opening may be provided at the top. The core 107 can be installed into the housing 105 through the opening. After the core 107 is installed in the housing, it can be sealed by a cover plate 108. A positive electrode terminal 101 and a negative electrode terminal 102 are respectively provided on the cover plate 108. The positive electrode terminal 101 is electrically connected to the positive electrode sheet, and the negative electrode terminal 102 is configured to be electrically connected to the negative electrode sheet. A heat exchange positive electrode terminal 103 and a heat exchange negative electrode terminal 104 are also provided between the positive electrode terminal 101 and the negative electrode terminal 103, and are configured to be electrically connected to both ends of a heat exchange plate 106 respectively. The battery of this embodiment is also provided with a heat exchange plate 106. In this embodiment, the heat exchange plate is configured to be generally rectangular, and the size of the heat exchange plate is substantially the same as that of the positive electrode sheet or the negative electrode sheet. The heat exchange plate 106 is accommodated in the internal space of the battery housing 105.

[0026] The heat exchange plate 106 in this embodiment includes a refrigerating sheet 1061, a heat sink 1062, and a thermoelectric semiconductor pair 20 disposed between the refrigerating sheet 1061 and the heat sink 1062. The thermoelectric semiconductor pair 20 is configured as a Peltier element, and the entire heat exchange plate is made of a thermoelectric material. At one end of the heat exchange plate 106 close to the battery top cover 108, a positive terminal 1064 and a negative terminal 1063 are respectively provided. The positive terminal 1064 is configured to be electrically connected to the heat exchange positive terminal 103 of the battery, and the negative terminal 1063 is configured to be electrically connected to the heat exchange negative terminal 104 of the battery. The refrigerating sheet 1061 and the heat sink 1062 of the heat exchange plate 106 face each other, the refrigerating sheet 1061 is disposed close to the battery electrode plate, and the heat sink 1062 is disposed close to the battery housing 105. A plurality of thermoelectric semiconductor pairs 20 connected in series with each other are disposed between the refrigerating sheet 1061 and the heat sink 1062.

[0027] The heat exchange plate 106 in this embodiment is formed as a thermoelectric semiconductor cooler, which is a cooler made by using the Peltier effect that heat absorption and heat release phenomena occur when an electric current passes through the junction of two different conductors. The principle of the Peltier effect is that the energy levels of electrons are different between different conductors. Therefore, when moving between two conductors, energy level transitions will occur, and energy will be absorbed or released in the form of heat, so an effect of heating at one end and cooling at the other end is presented. The Peltier element used in this embodiment is the thermoelectric semiconductor pair 20 as Figure 3-4 shown. The thermoelectric semiconductor pair 20 / Peltier element 20 includes a P-type semiconductor 204, an N-type semiconductor 203, a first conductive layer 201, a second conductive layer 202, and a third conductive layer 203. When the battery in this embodiment is used in a battery system, when the temperature detection unit of the battery system detects that the core temperature inside the battery 10 is too high, the battery system will control the refrigeration switch K1 of the battery to be turned off, connect the heat exchange positive terminal 103 and the heat exchange negative terminal 104, and simultaneously connect to an external power supply 400. The current generated by the external power supply 400 sequentially passes through the third heat conducting sheet 203 and flows to the N-type semiconductor 205, the first heat conducting sheet 201, the P-type semiconductor 204, and the second heat conducting sheet 202. When the current passes through the electric couple formed by the series connection of the N-type semiconductor 205 and the P-type semiconductor 204, the carriers in the semiconductor will carry the heat (the heat generated by the battery heating) from one end to the other end, and heat will be released and absorbed at both ends of the electric couple respectively, that is, heat absorption occurs at the node of the first heat conducting sheet 201 and the N-type semiconductor 205, and heat release occurs at the node of the second heat conducting sheet and the P-type semiconductor 204, thereby realizing heat transfer. Specifically, the first heat conducting sheet 201 performs refrigeration, and the second conductive sheet 202 performs heat dissipation.

[0028] For the battery 10 in this embodiment, when the heat exchange plate 106 is connected to an external power supply, the cooling fin 1061 of the heat exchange plate conducts the heat on the battery cell to the first heat conducting layer 201 of the thermoelectric semiconductor. Since the first heat conducting layer 201 in the thermoelectric semiconductor has a cooling effect, the heat is quickly conducted from the first heat conducting sheet 201 to the second heat conducting sheet / the third heat conducting sheet, and the heat absorbed by the second heat conducting sheet / the third heat conducting sheet is quickly conducted to the outside of the battery case through the heat sink 1062.

[0029] Furthermore, in order to achieve a better effect of cooling the battery, heat exchange plates 106 are respectively arranged on two sides of the battery, so that rapid cooling can be respectively carried out at both ends of the battery. However, optionally, only one heat exchange plate 106 can also be arranged in the battery of this embodiment, and the number of heat exchange plates can be flexibly selected and set according to the specific environment in which the battery is used, not limited to one or two, and can also be set to 3 or more.

[0030] In this embodiment, in order to prevent the direct contact between the positive electrode plate or the negative electrode plate of the battery and the P-type and N-type semiconductor materials, a layer of insulating but heat-conducting layer material, such as polyimide film or ceramic plate, can be further arranged on the outer layer of the heat exchange plate 106 to better protect the thermoelectric semiconductor material in the heat exchange plate, so as to realize the uniform transmission of the heat flux density inside the heat exchange plate structure, and thus maximize the thermoelectric performance of the material.

[0031] In order to further improve the heat conduction effect of the heat exchange plate 106 on the battery heat, a first heat conducting structural adhesive surface and a second heat conducting structural adhesive surface can be respectively arranged outside the heat exchange plate 106; the first heat conducting structural adhesive surface is attached to the side surface of the battery cell electrode plate, and the second heat conducting structural adhesive surface is attached to the large surface of the battery case, so as to further realize the soft contact between the heat transfer interfaces, reduce the thermal resistance, improve the heat transfer efficiency, and further accelerate the heat transfer rate. In addition, the heat exchange plate 106 itself can be adjusted through formula and density, and still maintain good heat conduction performance when not connected to an external power supply, so as to realize the function of dissipating heat inside the battery under normal working conditions.

[0032] The battery in this embodiment uses a heat exchange plate made of thermoelectric material inside. The battery has a fast cooling rate, can meet the demand for large heat dissipation in a short time, realizes the rapid cooling of the battery, and prevents the occurrence of thermal runaway. When the battery in this embodiment is used in a battery system and used in cooperation with a liquid cooling system outside the battery, it can realize the rapid and persistent heat dissipation of the battery under extreme working conditions, delay the occurrence of thermal runaway, and extend the safe operation time of the battery.

[0033] For the battery system composed of the batteries in this embodiment, the positive terminal 1063 and negative terminal 1064 of the heat exchange plate 106 are electrically connected to the heat exchange positive terminal 103 and heat exchange negative terminal 104 on the battery top cover respectively. The heat exchange plates in each battery are connected in series with each other through the heat exchange positive terminal and heat exchange negative terminal. An external switch K1 is provided in the battery system to simultaneously disconnect or connect the heat exchange plates in each battery. When the temperature detection unit in the battery system detects that the temperature inside the battery is too high, the external switch closes, and the refrigeration circuit of the heat exchange plate is connected to cool the battery to quickly dissipate the heat inside the battery to achieve temperature reduction. In the battery system, to prevent the external switch K1 from failing to be normally switched on or off due to a fault, which may affect the refrigeration work of the thermoelectric cooler, a second external switch K2 is also provided in the battery system. Thus, even when the first external switch K1 fails to work properly due to mechanical failure or other reasons, the second external switch K2 can also control the heat exchange plate, thereby achieving double protection of the heat exchange plate in the battery system and effectively ensuring the normal operation of the battery heat exchange plate in the battery system. In this embodiment, only one external switch K1 is required for multiple batteries in the battery system to control the thermoelectric coolers in all batteries. The battery system has high control efficiency, low cost, and a simple structure. Embodiment

[0034] The same parts as those in Embodiment 1 will not be described again. Only the differences from Embodiment 1 will be described here. As Figure 7-9 shown. Only one heat exchange positive terminal 303, positive terminal 301, and negative terminal 302 are provided on the battery 30 in this embodiment. One end of the heat exchange plate 306 is directly connected to the battery negative plate, and the other end of the heat exchange plate 306 extends out and is connected to the heat exchange positive terminal 301 on the top cover. When the battery in this embodiment is applied in the battery system, a plurality of external switches K1, K2, K3... Kn corresponding to the batteries are provided in the battery system, so that the battery system can separately control the heat exchange plates in each battery unit. When it is detected in the battery system that the temperature in a certain battery is particularly high, the corresponding external switches K1, K2, K3... Kn can be controlled to connect the heat exchange plate to the external power supply to achieve a refrigeration effect, so as to achieve the effect of cooling the inside of the battery. To achieve precise control of the temperature in each battery unit and thus efficiently maintain the temperature control of the entire battery system, and achieve precise control of the temperature of the battery system.

[0035] The above embodiments of the present utility model are merely examples for clearly illustrating the present utility model, rather than limitations on the implementation manners of the present utility model. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation manners here. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the claims of the present utility model.

Claims

1. A battery, comprising: a cell body provided with a positive electrode tab, a negative electrode tab, and a separator disposed between the positive electrode tab and the negative electrode tab; a housing configured to accommodate the cell body, including a top cover disposed on the top of the housing; a positive electrode post electrically connectable to the positive electrode tab and disposed on the top cover; a negative electrode post electrically connectable to the negative electrode tab and disposed on the top cover; a heat exchange plate disposed within the housing, characterized in that the heat exchange plate includes a refrigerating sheet and a heat dissipating fin disposed opposite to each other, the refrigerating sheet is disposed opposite to the cell body to absorb heat dissipated by the cell body, and the heat dissipating fin is disposed opposite to the housing to discharge the absorbed heat out of the housing.

2. The battery according to claim 1, characterized in that, The heat exchange plate is made of a thermoelectric material.

3. The battery according to claim 1, wherein A thermoelectric semiconductor is disposed between the refrigerating sheet and the heat conducting fin.

4. The battery according to claim 1, wherein, There are two heat exchange plates provided.

5. The battery according to claim 1, wherein The battery further includes a heat exchange pole post disposed on the top cover, and the heat exchange plate is electrically connected to the heat exchange pole post.

6. The battery according to claim 5, characterized in that, The heat exchange pole post includes a heat exchange positive pole post and a heat exchange negative pole post.

7. The battery according to claim 6, characterized in that, One end of the heat exchange plate is electrically connected to the heat exchange positive pole post, and the other end of the heat exchange plate is electrically connected to the heat exchange negative pole post.

8. A battery system, characterized in that, Including a plurality of batteries as described in any one of claims 1-7, an external power source, and a control switch, the control switch can control the disconnection and connection of the heat exchange plate and the external power source.

9. The battery system according to claim 8, wherein, There are a plurality of control switches provided, and each control switch can independently control the disconnection and connection of the heat exchange pole post in the corresponding battery and the external power source.

10. The battery system according to claim 8, wherein The control switch can simultaneously control the connection and disconnection of the heat exchange plates in a plurality of batteries within the battery system and the external power source.

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