WO2010045876A1

WO2010045876A1 - Protection device, protection device system and protection method of power battery

Info

Publication number: WO2010045876A1
Application number: PCT/CN2009/074568
Authority: WO
Inventors: 李光明
Original assignee: Li Guangming
Priority date: 2008-10-22
Filing date: 2009-10-22
Publication date: 2010-04-29

Abstract

A protection device of power battery, a protection device system of power battery and a protection method of power battery are provided. The device includes a battery box which is sealed, wherein liquid is provided inside the box and a battery group is provided in the liquid inside the battery box. The device is capable of balancing the environment temperature of the cells in the battery group so as to prevent performance of the cells from decreasing due to the environment temperature difference between the cells, and prolong the usable life of the power battery. Further, the liquid seal performance of the liquid can act the fire proof effect.

Description

Power battery protection device, protection device system and protection method

The present invention relates to a power system of an electric vehicle or a hybrid electric vehicle, and more particularly to a power battery protection device, a protection device system, and a protection method. Background technique

The power battery system of an electric vehicle or a hybrid electric vehicle is a group of battery packs. The problem of the balance of the battery pack is a common worldwide problem. In the process of charging and discharging, the single battery has problems, such as failure to properly charge and discharge, Causes the short board effect of the entire battery pack, and a vicious circle. The reasons are various, the reasons for the production process, the reasons for the raw materials and the reasons for the use. In response to this problem, there are various real-time charging and discharging management systems in the industry to identify the problematic single cells and repair or replace them to ensure the normal operation of the entire battery pack, but this is only passive management. Technology, as a remedial technical solution, cannot prevent the occurrence of short board effects.

In fact, an important reason for the imbalance of the battery pack is that the battery pack is located in different parts of the vehicle, and is affected by the ambient temperature of different parts of the vehicle. There is a large environmental temperature difference between the single cells, and the prior art has However, there is a lack of protection for the working environment of the battery pack during charging and discharging, and in particular, there is a lack of balanced temperature protection for the environment in which the battery pack is located. Summary of the invention

In order to solve the problem that the performance of the single battery caused by the environmental temperature difference between the single cells in the charging and discharging process of the prior art causes the whole battery to form a short board effect, the present invention provides a power battery protection device and a protection device. The system and the protection method are used for equalizing the ambient temperature of each single battery in the battery pack, avoiding the problem that the temperature difference causes the performance of the single battery to decrease, and preventing the occurrence of the short board effect. Technical solutions:

A power battery protection device for protecting a battery pack of a power battery is characterized in that it comprises a closed battery case containing a liquid therein, and a liquid inside the battery case is immersed in the battery pack.

A water pump is also disposed inside the battery case.

Also included is a liquid tank containing a liquid, the liquid tank being in communication with the battery tank through two or more liquid conduits, the liquid conduit being provided with a circulating water pump. The liquid is a non-conductive liquid.

The liquid is an antifreeze type non-conductive liquid.

The liquid is ethylene glycol.

An insulating sealing device capable of isolating the liquid is disposed at the positive and negative electrodes of each of the unit cells of the battery pack.

Also included is a pedestal located inside the battery case for securing the battery pack.

The housing of the battery case is made of metal; and/or the outer surface of the battery case is coated with a fireproof insulation layer and/or the inner surface of the battery case is coated with a fireproof insulation layer.

The fireproof insulation layer is made of high silica glass fiber composite material.

The battery case is a double-layered housing structure, the inner layer housing is made of a metal material, and the outer layer housing is made of a fireproof and heat-insulating material.

A sealed space is formed between the inner layer and the outer layer of the double-layered casing, and the sealed space is air or an inert gas or a vacuum.

Also included is a condensing structure for cooling the liquid, the condensing structure being a portion of the air conditioning condensing duct of the vehicle in which the power battery protection device is located, which is in contact with the liquid in the battery case through the battery case.

The battery box is internally provided with a temperature sensor for monitoring the temperature of the internal liquid therein, and the battery box or the liquid tank or the liquid pipeline is provided with a heater, and the vehicle in which the power battery protection device is located is equipped with an electric fan, the temperature A sensor is coupled to the heater and the electronic fan, the liquid tank being disposed within a cooling range of the electronic fan.

A power battery protection device system for protecting a battery pack of a power battery, the battery pack comprising a plurality of battery groups connected in series or in parallel with each other, wherein the power battery protection device system includes a plurality of batteries corresponding to the battery A plurality of the above-described power battery protection devices that are connected by a liquid passage, the liquid interior of each of the power battery protection devices being immersed in the group of battery groups.

The battery compartments of the plurality of power battery protection devices are connected in series through a liquid passage, and the adjacent two battery compartments are connected by two or more liquid passages, and the liquid passage is provided with a circulating water pump .

A method of protecting a power battery, characterized in that a battery pack of the power battery is immersed in a liquid interior.

The battery pack includes a plurality of battery packs connected in series or in parallel with each other, and the battery packs of the respective groups are separately dip Enter the interior of the interconnected liquid.

The liquid is a non-conductive liquid.

The liquid is an antifreeze type non-conductive liquid.

The liquid is a recyclable liquid.

Technical effect:

The invention provides a power battery protection device, comprising a watertight sealed battery box and a liquid contained inside the battery box, the battery pack of the power battery is immersed in the liquid, because the thermal conductivity of the liquid is significantly better than the air Therefore, the environmental temperature difference between the single cells of the battery pack immersed therein is significantly reduced, thereby avoiding the problem that the single battery cannot be normally charged and discharged due to the temperature difference, not only preventing the occurrence of the short board effect, but also prolonging the battery. Secondly, the battery pack in the discharge state generally corresponds to the vehicle in the running state, and the power battery protection device located inside the vehicle will move together with the traveling vehicle, and the acceleration, deceleration, bump, etc. generated by the movement will enhance the liquid. The fluidity in the battery box can promote the temperature balance between the liquids, thereby further reducing the environmental temperature difference between the individual cells of the battery pack; in addition, the battery pack is immersed in the liquid, and the liquid sealing property of the liquid is used to make the battery The group is isolated from oxygen and also avoids fires.

Preferably, the battery box is internally provided with a water pump for forcibly circulating the liquid inside the battery box to ensure that the individual cells of the battery pack are in a balanced temperature environment; or the power battery protection device further includes a loading device a liquid tank having a liquid, the liquid tank is connected to the battery box through two or more liquid pipes, and a circulating water pump is arranged on the liquid pipe, so that the liquid in the battery box and the liquid in the liquid tank form a circulation, and the battery pack is also ensured. Each individual cell is in a balanced ambient temperature. In addition, a base frame may be disposed inside the battery protection device for fixing the battery pack while immersing the battery pack in the liquid in an all-round manner, thereby improving the balance effect of the liquid on the temperature of the battery pack, and improving the fluidity of the liquid. .

In order to prevent leakage or short circuit of the battery pack in the liquid, it is preferred to use a non-conductive liquid, or an insulating sealing device for isolating the liquid at the positive and negative terminals of each of the single cells. Further, the liquid may be selected from an anti-freeze type non-conductive liquid to adapt to work under low temperature conditions, that is, to prevent the liquid from freezing at a low temperature and to lose the effect of equalizing the ambient temperature of the battery pack. Preferably, the liquid is ethylene glycol and has a melting point of about minus 13 degrees Celsius. It is a non-conductive liquid and is inexpensive and readily available.

The housing of the battery case is preferably made of metal, and can shield the external electromagnetic radiation of the battery pack while ensuring sufficient strength of the battery case; and the outer surface and/or the inner surface of the battery case is coated with fireproof insulation The material is used to block the outside temperature, to avoid the influence of the environment of the vehicle on the power battery protection device and its internal liquid, and also has a fireproof function.

The battery case can also be a double-layered housing structure, the inner layer of the housing is made of metal for shielding the electromagnetic radiation of the battery pack; the outer casing is made of fireproof and insulating material, which is used for blocking the external temperature and avoiding the environment and the power of the vehicle. The battery protection device and the internal liquid are affected, and have a fireproof function. A closed space is formed between the inner layer and the outer layer of the double-layer structure, and the air or inert gas or vacuum is in the closed space, and the thermal conductivity under the conditions of air, inert gas and vacuum is sequentially lowered, so that the heat preservation effect is sequentially increased.

Further, it further includes a condensing structure for cooling the liquid, the condensing structure being a portion where the air conditioning condensing duct of the vehicle in which the power battery protecting device is located passes through the battery case and the liquid in the battery case. When the external high-temperature car air conditioner is turned on, the condensing structure acts to cool the liquid in the battery box. When the power battery protection device includes the liquid tank, the liquid tank is disposed in the cooling range of the electronic fan, and when the temperature sensor detects that the liquid temperature is higher than the upper temperature limit, the electronic fan is activated to strongly cool the liquid in the liquid tank, and The liquid circulation lowers the temperature of the liquid in the battery compartment below the upper temperature limit. When the temperature sensor detects that the liquid temperature is lower than the lower temperature limit, the starter heater heats the liquid temperature in the battery compartment above the lower temperature limit.

When the battery pack is grouped into groups of batteries connected in series or in parallel with each other, the present invention provides a power battery protection device system, which is configured to correspond to a plurality of battery protection devices connected by a liquid passage corresponding to the battery group. The inside of the liquid in the power battery protection device is immersed in a power battery protection device to ensure that the battery groups of the groups are at similar or even the same ambient temperature. Preferably, the battery compartments of the plurality of power battery protection devices are connected in series through the liquid passage, and the adjacent two battery compartments are connected by two or more liquid passages, and the liquid passage is provided with a circulating water pump. The purpose is to make the liquid inside each battery box form an integral liquid circulation, to ensure that there is no temperature difference between the liquids in each battery box, and further ensure that each battery group of each group of battery groups, groups or groups of batteries is located. The balance of the ambient temperature, thus effectively avoiding the occurrence of single cell problems.

The invention also provides a method for protecting a power battery, wherein the battery pack of the power battery is immersed in the liquid, and the thermal conductivity of the liquid is superior to that of the air, so that the environmental temperature difference between the single cells of the battery pack immersed therein is significantly reduced. Thereby, the problem of the single battery is avoided, and the service life of the battery is prolonged. Secondly, the liquid sealing property of the liquid is used to isolate the battery pack from oxygen, thereby avoiding the occurrence of fire. When the battery pack is grouped into groups of batteries connected in series or in parallel, each group of batteries is separately immersed in the liquid connected to each other to ensure the balance of the ambient temperature of each group of battery packs. In order to prevent leakage or short circuit of the battery pack or battery group in the liquid, it is preferred to use a non-conductive liquid. Further, the liquid may be selected from an anti-freeze type non-conductive liquid to adapt to work at a low temperature, that is, to prevent the liquid from freezing at a low temperature and to lose the effect of equalizing the ambient temperature of the battery pack. Preferably, the liquid is a recyclable liquid, further ensuring that the individual cells of the battery pack or battery group are in a balanced temperature environment. DRAWINGS

1 is an embodiment of a power battery protection device of the present invention;

2 is an embodiment of a power battery protection device system of the present invention;

Figure 3 is another embodiment of a power battery protection device of the present invention;

Figure 4 is a top view of the battery pack and the base frame of Figure 3. The reference numerals are exemplified as follows:

100-power battery protection device, 101-battery case, 102-fireproof insulation, 103-air conditioning condenser, 104-ethylene glycol, 105-battery, 106-pump;

200-power battery protection system, 201, 20Γ-battery case, 202, 202' - fire insulation, 203-air conditioning condenser, 204-ethylene glycol, 205, 205'-battery group, 206-circulating pump , 207, 207'- liquid passage;

300-power battery protection device, 301-battery case inner casing, 302-battery case outer casing, 303-inert gas, 304-ethylene glycol, 305-battery pack, 306-circulating water pump, 307-liquid tank , 308, 308, - liquid piping, 309 - temperature sensor, 310 - heater, 311 - electronic fan, 312 - pedestal. detailed description

The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Example 1

As shown in FIG. 1, an embodiment of a power battery protection device of the present invention is shown. The power battery protection device 100 includes a battery case housing 101, an ethylene glycol 104, and a water pump 106. The battery pack 105 is placed in electricity Inside the glycol 104 in the tank casing 101, the water pump 106 forcibly circulates the ethylene glycol 104 in the battery casing 101, so that the individual cells of the battery pack 105 are in an environment of balanced temperature, thereby avoiding The emergence of a single cell problem prevents the occurrence of short board effects and extends the life of the battery. In addition, the liquid-sealed battery pack 105 is isolated from oxygen gas, and fire is also prevented. The air conditioning condenser 103 is in contact with the glycol 104 in the battery case through the battery case 101. When the external high temperature car air conditioner is turned on, the air conditioning condenser 103 can cool the ethylene glycol 104. Of course, the portion of the air conditioning condenser located inside the glycol 104 is preferably disposed away from the battery pack 105 to avoid partial overcooling of the battery pack 105, resulting in a temperature differential between the individual cells.

The battery case 101 is preferably made of a metal material such as aluminum and stainless steel to shield the electromagnetic radiation from the battery pack 105 outward. The outer surface of the battery case 101 is coated with a fireproof insulation layer 102 to isolate the influence of the external environment on the ethylene glycol 104. For example, a high silica glass fiber composite material can be used, and the material has good heat preservation effect, and experiments have shown that the material It can block the high temperature of 1100 degrees Celsius in ten minutes and has fireproof function. The fire insulating layer 102 may also be applied to the inner surface of the battery case 101 or may be coated with a fire insulating layer on the inner and outer surfaces of the battery case.

In addition, the liquid in the battery case may be other than ethylene glycol. However, it is preferable to use a non-conductive liquid in order to prevent leakage and short-circuiting of the battery; of course, if an insulating sealing device capable of isolating the liquid is provided at the positive and negative terminals of each unit cell of the battery pack, the selection of the liquid is not limited thereto. If the vehicle needs to travel in a low temperature environment, the liquid is preferably an antifreeze type liquid to prevent the liquid from freezing at a low temperature and losing the effect of balancing the ambient temperature of the battery pack. The choice of liquid is equally applicable to the following examples. Example 2

As shown in FIG. 2, it is an embodiment of a power battery protection device system according to the present invention. The power battery in this embodiment includes two groups of battery groups 205 and 205' connected in series or in parallel (not shown in FIG. 2). Correspondingly, the battery protection device system 200 includes two battery compartments connected in series, and two sets of battery packs 205 and 205' are respectively placed in the two battery compartments. As in the first embodiment, the outer surface of the battery case 201 (201') is coated with a fireproof insulating layer 202 (202'), and the battery case 201 (201') is filled with ethylene glycol 204. However, in the present embodiment, the two battery case housings 201 and 20' are communicated through the two liquid passages 207 and 207' such that the ethylene glycol 204 in the battery case casing 201 and the ethylene glycol 204 in the battery case casing 20'' Connected. The liquid passages 207 and 207' are used with the battery case 201 (201') The same material, preferably, the outer surfaces of the liquid passages 207 and 207' are also coated with a fireproof insulation layer, and the fire insulation layer can be selected from the same fireproof insulation material as the outer surface of the battery case 201 (201'). 202 (202') to prevent the external environment from affecting the glycol and battery group 205 (205') in the battery compartment by the influence of the glycol 204 in the liquid passage 207 (207'). The air conditioning condensing duct 203 is respectively in contact with the ethylene glycol 204 in the casing through the battery case casings 201 and 201'. When the external high temperature starts the car air conditioner to be turned on, the air conditioning condensing pipe 203 can cool the ethylene glycol 204. Similarly, the portion of the air conditioning condenser located within the glycol 204 is preferably disposed remotely from the battery pack 205 (205') to avoid partial subcooling of the battery pack 205 (205'), causing a temperature differential between the individual cells.

Preferably, a circulating water pump 206 is provided in the liquid passage 207' to activate the circulating water pump 206 such that the glycol 204 in the battery case housing 201 and the glycol 204 in the battery case 201' pass through the liquid passage 207. Forming an overall cycle with 207' to equalize the temperature of the glycol in which battery packs 205 and 205' are located, avoiding the occurrence of single cell problems and preventing the occurrence of short board effects. Example 3

As shown in FIG. 3, it is another embodiment of a power battery protection device of the present invention. The power battery protection device 300 includes a battery case inner casing 301, a battery case outer casing 302, a glycol 304, a liquid tank 307, a liquid pipe 308 (308'), and a circulating water pump 306. The battery case inner casing 301 is made of a metal material, such as aluminum or stainless steel, for shielding electromagnetic radiation of the battery pack 305; the outer casing 302 of the battery case is a fireproof heat insulating material, such as a high silica glass fiber composite material, of course, Other fireproof insulation materials are used to block the outside temperature, to avoid the influence of the environment of the vehicle on the internal glycol battery 304 and the battery pack 305 of the power battery protection device, and also have a fireproof effect. A sealed space is formed between the battery case outer casing 302 and the battery case inner casing 301, and the air may be air in the sealed space, but is preferably an inert gas or a vacuum state to further enhance the heat insulating effect. A base frame 312 (see FIG. 4) is further disposed in the inner casing 301 of the battery case for fixing the individual cells of the battery pack 305 while immersing the individual cells of the battery pack 305 into the ethylene glycol in all directions. In 304, the equalization effect of the ethylene glycol 304 on the ambient temperature of the battery pack 305 is increased. The inner casing 301 of the battery box communicates with the liquid tank 307 through two liquid pipes 308 and 308', and a circulating water pump 306 is disposed in one of the liquid pipes 308 to make the ethylene glycol in the inner casing 301 of the battery case. 304 forms a liquid circulation with the glycol 304 in the liquid tank 307, and further circulates the ethylene glycol of each part at a similar temperature or even the same temperature by liquid circulation, thereby further protecting Each of the individual cells of the battery pack 305 is at a balanced ambient temperature, and the temperature of the glycol in the battery compartment can be adjusted by changing the temperature of the glycol in the liquid tank.

In addition, in order to prevent the continuous influence of the external environment on the battery box, the overall temperature of the glycol 304 in the battery box is raised or lowered, and a temperature sensor for monitoring the temperature of the glycol 304 is disposed in the inner casing 301 of the battery case. 309, when the temperature of the ethylene glycol is higher than the upper temperature limit, the electronic fan 311 is activated to forcibly cool the ethylene glycol in the liquid tank 307, and the liquid circulation is performed to gradually cool the ethylene glycol 304 in the inner casing of the battery box. Until a temperature below the upper temperature limit; when the temperature of the ethylene glycol is below the lower temperature limit, the heater 310 is activated to heat the glycol 304 until it is above a certain temperature after the lower temperature limit. The electronic fan 311 is a standard configuration of the existing vehicle and is located at the front end of the vehicle, so that the liquid tank 307 is disposed within the cooling range of the electronic fan 311 at the front end of the vehicle; the heater 310 may be disposed in the inner casing 301 of the battery case or the liquid tank 307 Within the inner or liquid conduit 308 (308'), it is contemplated to avoid the effects of local overheating of the glycol 304 on the battery pack 305. Preferably, the heater is disposed within the liquid conduit 308 (308') or the liquid tank 307 and is circulated through the liquid. The glycol 304 in the inner casing of the battery case is gradually heated.

Further, the liquid pipe 308 (308') may adopt the inner and outer double-shell structure of the battery case and form a closed space between the inner and outer casings, and the air may be air in the closed space, but is preferably an inert gas or a vacuum state, Further, the heat preservation effect is enhanced; the liquid pipe 308 (308') can also be coated with the fireproof heat insulation layer outside the metal casing of the second embodiment, and the heat insulation and fireproof effect can also be achieved.

Claims

Rights request

A power battery protection device for protecting a battery pack of a power battery, characterized by comprising a closed battery case containing a liquid inside, and a liquid inside the battery case is immersed in the battery pack.

The power battery protection device according to claim 1, wherein a water pump is further provided inside the battery case.

The power battery protection device according to claim 1, further comprising a liquid tank containing a liquid, wherein the liquid tank communicates with the battery box through two or more liquid pipes, A circulating water pump is arranged on the liquid pipeline.

The power battery protection device according to any one of claims 1 to 3, wherein the liquid body is a non-conductive liquid.

The power battery protection device according to claim 4, wherein the liquid is an antifreeze type non-conductive liquid.

The power battery protection device according to claim 5, wherein the liquid is ethylene glycol.

The power battery protection device according to any one of claims 1 to 3, characterized in that the positive and negative electrodes of the respective battery cells of the battery pack are provided with an insulating sealing device capable of isolating the liquid.

The power battery protection device according to any one of claims 1 to 3, further comprising a base frame located inside the battery case for fixing the battery pack.

The power battery protection device according to any one of claims 1 to 3, wherein the housing of the battery case is made of metal; and/or the outer surface of the battery case is coated with fireproof insulation The inner surface of the layer and/or the battery case housing is coated with a fire resistant insulation layer.

10. The power battery protection device according to claim 9, wherein the fire insulating layer is made of a high silica glass fiber composite material:

The power battery protection device according to any one of claims 1 to 3, wherein the battery case is a double-layered housing structure, the inner layer housing is made of a metal material, and the outer layer housing is Fireproof insulation material.

The power battery protection device according to claim 11, wherein a sealed space is formed between an inner layer and an outer layer of the double-layered casing, and the sealed space is air or an inert gas or a vacuum.

The power battery protection device according to any one of claims 1 to 3, characterized in that A condensing structure for cooling the liquid, the condensing structure being a portion of the air conditioning condensing duct of the vehicle in which the power battery protection device is located, which is in contact with the liquid in the battery box through the battery case.

The power battery protection device according to claim 3, wherein the battery case is internally provided with a temperature sensor for monitoring the temperature of the internal liquid therein, and the battery case or the liquid tank or the liquid pipe is provided with a heater The vehicle in which the power battery protection device is located is equipped with an electronic fan, and the temperature sensor is connected to the heater and the electronic fan, and the liquid tank is disposed within a cooling range of the electronic fan.

15. A power battery protection device system, a battery pack for protecting a power battery, the battery pack comprising a plurality of battery groups connected in series or in parallel, wherein the power battery protection device system comprises a plurality of The plurality of battery packs are powered by the liquid passages of the power battery protection device of claims 1-14, the liquid interior of each of the power battery protection devices being immersed in the set of battery packs.

The power battery protection device according to claim 15, wherein the battery compartments of the plurality of power battery protection devices are connected in series through a liquid passage, and the two adjacent battery boxes pass between two Or two or more liquid passages are connected, and the liquid passage is provided with a circulating water pump.

The method of protecting a power battery according to claim 17, wherein the battery pack comprises a plurality of battery packs connected in series or in parallel, each of the battery packs being immersed in a liquid body that communicates with each other.

The method of protecting a power battery according to claim 17 or 18, wherein the liquid is a non-conductive liquid.

The method of protecting a power battery according to claim 19, wherein the liquid is an anti-freeze type non-conductive liquid.

The method of protecting a power battery according to claim 20, wherein the liquid is a recyclable liquid.