TWI441369B - Lithium battery module - Google Patents

Description

Lithium battery module

The invention relates to a lithium battery module, in particular to a lithium battery module which can maintain a stable thermal expansion rate of the battery core and improve heat conduction efficiency.

In order to supply electric power for products such as electric vehicles and electric hand tools that require a large starting current, lithium batteries are aimed at high performance and large capacity, but they also have two problems: thermal expansion and contraction, and heat dissipation. .

Regarding thermal expansion and contraction, if the positive and negative electrodes of a lithium battery do not apply a moderate clamping force for a long period of time, they will naturally expand and contract, and after a long period of time, they will have a large rate of change in internal structure and affect their life. . Therefore, it is generally covered with foam, but the clamping force of the foam is unstable, and the variation of the thermal expansion and contraction is natural, and the expansion rate cannot be controlled within a certain range.

As for the heat dissipation, the heat generated by the lithium battery is radiated into the air through the heat sink. Since the heat sink and the base constituting the heat sink are separately molded and then combined, it is difficult to make the two contact with each other, and as a result, the heat transfer efficiency is deteriorated due to poor contact. Further, in order to improve the heat dissipation efficiency, a copper pipe for circulating cooling water is embedded in the interior of the base, and the upper and lower portions are sandwiched and fixed by an aluminum alloy seat cover having a groove corresponding to the curved shape of the copper pipe. Although this design helps to continuously remove heat from the heat sink, the manufacturing cost is high, and a gap is formed between the upper and lower seat covers and the copper pipe, so that heat transfer efficiency is lowered.

The present invention has been made to solve the above problems, and an object thereof is to provide a lithium battery module having a self-adjusting function, which can maintain a stable rate of expansion of a battery cell and prolong its service life.

Another object of the present invention is to provide a lithium battery module having a simple but effective heat sink that can reduce manufacturing costs while improving heat transfer efficiency.

The lithium battery module of the present invention comprises a casing having a bottom wall and opposite side walls; a radiator disposed in the casing, having a base and a plurality of fins extending upward from the base, each A core chamber is defined between two adjacent heat sinks; a plurality of battery cells, each battery core is disposed in a core chamber of the heat sink, and two sides of the battery core respectively define heat dissipation of the core chamber And a self-adjusting device having a fixing plate supported on one of the side walls of the outer casing, a movable plate facing the fixing plate and supported on one of the outer fins of the heat sink, and a plurality of elastic members being clamped Holding a tension between the fixed plate and the movable plate to apply pressure to each of the battery cells sandwiched between the two heat sinks through the movable plate, thereby stabilizing and limiting the battery cells The rate of change in expansion.

The lithium battery module further includes a cooling system including a bottom cover having a flow path sandwiched between a bottom wall of the outer casing and a base of the heat sink, and a driving cooling water in the flow path A water pump that circulates and absorbs heat and a device that exchanges the cooling water with the external environment.

The lower portion of the heat sink forms a buffering angle to alleviate the impact when the battery core expands.

The fixing plate of the self-adjusting device comprises a plurality of guiding sleeves, each guiding sleeve is composed of two concentric inner guiding sleeves and outer guiding sleeves, and an annular gap is defined between the inner guiding sleeve and the outer guiding sleeve; the movable panel has a plurality of sleeves, each sleeve being sleeved into a gap of the guide sleeve to press the elastic member disposed in the gap to tension the elastic member.

In another embodiment, the fixing plate of the self-adjusting device comprises a plurality of guiding sleeves, the movable plate has a plurality of sleeves, and each sleeve is sleeved on an outer circumference of the guiding sleeve to press the sleeve around each guiding sleeve The elastic member causes the elastic member to be tensioned.

In another embodiment, the fixing plate of the self-adjusting device comprises a plurality of guiding sleeves, the movable plate has a plurality of sleeves, and each sleeve is sleeved into a guiding sleeve to press the elasticity disposed in each guiding sleeve And the elastic member is tensioned.

The elastic member may be a compression spring, or may be made of a superior rubber.

The effect of the present invention in comparison with the conventional technology is that the expansion rate of the battery cell is stabilized on the one hand by the clamping force generated by an elastic member, preventing excessive expansion and affecting the life, and the battery core can also be used on both sides. The heat sink forms a close contact, and the heat generated by the heat sink is transmitted to the heat sink to prevent the battery core from overheating. Moreover, the bottom cover provided with the cooling water flow path is clamped between the bottom wall of the outer casing and the base of the integrated heat sink, so that the bottom cover and the heat sink can maintain reliable contact, thereby reducing manufacturing cost and improving heat conduction efficiency. .

The technical contents and other objects and features of the present invention will be fully understood from the following description of the embodiments.

The first figure is the appearance of the "lithium battery module" 10 of the present invention, the second figure is its component disassembled state, the third figure is its cross section, and the fourth figure is a partial enlarged cross section of the self-adjusting mechanism for explaining the present invention. Technical content, wherein the directions of up, down, left, and right are based on the first figure. The lithium battery module 10 is mainly composed of a casing 20, a radiator 30, a plurality of battery cells 40 and a self-adjusting device 50. among them:

The outer casing 20 has a bottom wall 21, a left side wall 22 extending vertically upward from the left side of the bottom wall 21, and a right side wall 23 extending vertically upward from the right side of the bottom wall 21. In the case of indoor safe area, it is also possible to adopt an open type, and the front and rear side walls are omitted to facilitate heat dissipation.

The heat sink 30 is integrally formed of a material having high thermal conductivity such as copper or aluminum. The heat sink 30 is disposed inside the outer casing 20 and includes a base portion 31 and fins 32 extending vertically upward from a plurality of equally spaced positions of the base portion 31, wherein between each two adjacent fins 32 A core chamber 33 is defined for receiving the battery cells 40. In the preferred embodiment, each of the heat sinks 32 has a cushioning corner 34 at its lower portion for mitigating the impact of the battery core 40 when it is inflated.

The battery cells 40 are the same as the number of the core chambers 33 of the heat sink 30. Each of the battery cells 40 is disposed in a core chamber 33 and is in close contact with the fins 32 on both sides thereof for heat conduction to cause the battery cells 40 to be generated. The heat is transferred to the heat sink 32 where it is dissipated into the air by contact with a large amount of air to prevent heat from being accumulated and damaged. The battery cell 40 is mainly composed of a positive electrode, a negative electrode, a separator separating the positive and negative electrodes, and an electrolyte. Since the battery core 40 is a conventional technique, further explanation is not necessary.

The self-adjusting device 50 is clamped between the left side wall 22 of the outer casing 20 and the left side heat sink 32 of the heat sink 30, which can apply a predetermined clamping force to the battery core 40 to keep the rate of expansion change stable. Service life. In fact, the self-adjusting device 50 can also be placed between the right side wall 23 of the outer casing 20 and the right side heat sink 32 of the heat sink 30, without being limited by the left side. The self-adjusting device 50 includes a fixing plate 51, a movable plate 52 and a plurality of elastic members 53. A plurality of guide sleeves 54 are formed on the inner side of the fixing plate 51. Each of the guide sleeves 54 is composed of two concentric inner guide sleeves 55 and outer guide sleeves 56. An annular gap 57 is defined between the inner and outer guide sleeves 55, 56. . The movable plate 52 is provided with a corresponding plurality of sleeves 58. Each of the sleeves 58 is nested in the annular gap 57 of the guide sleeve 54, so that the movable plate 52 can support the fixed plate 51 to move left and right. The number of the elastic members 53 is identical to the number of the guide sleeves 54 and the sleeves 58. Each of the elastic members 53 is placed in the annular gap 57 of the guide sleeve 54 and is pressed by the sleeve 58 that fits into each gap 57. In a tensioned state, a predetermined pressure (the pressure is the elastic restoring force of the elastic member 53) is applied to each of the battery cells 40 sandwiched between the two fins 32 through the movable plate 52, thereby stabilizing And limiting the rate of change of expansion of the battery core 40, to avoid its excessive expansion and affect the service life.

In the embodiment of the drawings, the elastic member 53 uses a compression spring, but can also be made tubular by Urethane, which is not limited by the spring. Youli Glue is epoxy plastic hardened resin due to its natural rubber compression It is elastic, not easy to bend and easy to manufacture, so it can be used as a rubber instead of a spring. The installation method of the excellent rubber can be followed by the user of the compression spring. Other elastic members equivalent to the compression spring and the tubular superior rubber, including the elastic piece and the superior rubber other than the tubular shape, may be used, but the configuration of the guide sleeve 54 and the sleeve 58 is modified correspondingly to receive the equivalent elasticity. Pieces.

Again, the self-adjusting device 50 is not limited by the above embodiments, which may be of other different types. For example, the self-adjusting device 50a shown in Fig. 5 is provided with a plurality of guide sleeves 54a on the inner side of the fixed plate 51a, and a plurality of sleeves 58a are disposed on the outer side of the movable plate 52a, and each elastic member 53a surrounds the periphery of a guide sleeve 54a. And being tensioned by the sleeve 58a sleeved on the outside of each guide sleeve 54a.

In addition, as shown in the sixth embodiment, the self-adjusting device 50b is provided with a plurality of guide sleeves 54b on the inner side of the fixed plate 51b, and a plurality of sleeves 58b are disposed on the outer side of the movable plate 52b, and each elastic member 53b is disposed at one The inside of the guide sleeve 54b is pressed by the sleeve 58b fitted into each of the guide sleeves 54b to be tensioned.

In a preferred embodiment, the lithium battery module 10 further includes a cooling system 60 to continuously remove heat from the heat sink 30 to improve heat dissipation efficiency. As shown in the first to third figures, the cooling system 60 includes a bottom cover 61 sandwiched between the bottom wall 21 of the outer casing 20 and the base portion 31 of the heat sink 30, the upper surface of which is formed with The flow path 62 of the inflow port 63 and the outflow port 64 and the contact surface with the base portion 31 are reliably airtight by a packing 65. The cooling system 60 further includes a water pump (not shown) that drives cooling water (not shown) to circulate in the flow path 62 to absorb heat, and a device that heat-exchanges the cooling water with the external environment, such as a heat exchanger. Etc. (not shown). As such, a portion of the heat generated by the battery cell 40 is naturally dissipated into the air through the heat sink 30, and a portion is transferred to the bottom cover 61 of the cooling system 60 via the heat sink 30, and is absorbed by the cooling water circulating in the flow path 62, and The heat exchange device is used to promote heat in the cooling water to the air, ensuring that the battery core 40 does not overheat.

The lithium battery module 10 as described above is a lithium battery for commercial use after being attached and protected by a battery management system (BMS) and necessary circuits, including as an electric vehicle, hybrid electric power. The energy storage and driving power supply (very large current is required) for vehicles, electric motors, electric bicycles, electric ships, airplanes, uninterruptible power systems (UPS), electric hand tools, etc. The above battery management system, circuit and cover are not shown in the scope of the present invention and are not shown.

Of course, the above embodiments may be modified without departing from the scope of the invention, and all the matters included in the above description and the drawings are to be considered as illustrative and not limiting the scope of the invention. .

10. . . Lithium battery module

20. . . shell

twenty one. . . Bottom wall

twenty two. . . Left side wall

twenty three. . . Right side wall

30. . . heat sink

31. . . Base

32. . . heat sink

33. . . Core chamber

34. . . Angle

40. . . Battery core

50, 50a, 50b. . . Self-adjusting device

51, 51a, 51b. . . Fixed plate

52, 52a, 52b. . . Activity board

53,53a, 53b. . . Elastic part

54,54a, 54b. . . Bushing

55. . . Inner guide sleeve

56. . . Outer sleeve

57. . . gap

58,58a, 58b. . . Sleeve

60. . . cooling system

61. . . Bottom cover

62. . . Runner

63. . . Inflow

64. . . Outflow

65. . . pad

The first figure is an external view of the present invention.

The second figure is an exploded view of the components of the present invention.

The third figure is a longitudinal sectional view of the present invention.

The fourth figure is a partially enlarged cross-sectional view of the self-adjusting device of the present invention.

Figure 5 is a partially enlarged cross-sectional view showing another embodiment of the self-adjusting device of the present invention.

Figure 6 is a partially enlarged cross-sectional view showing still another embodiment of the self-adjusting device of the present invention.

10. . . Lithium battery module

20. . . shell

twenty one. . . Bottom wall

twenty two. . . Left side wall

twenty three. . . Right side wall

30. . . heat sink

31. . . Base

32. . . heat sink

33. . . Core chamber

34. . . Angle

40. . . Battery core

50. . . Self-adjusting device

51. . . Fixed plate

52. . . Activity board

60. . . cooling system

61. . . Bottom cover

62. . . Runner

65. . . pad

Claims (7)

A lithium battery module comprising: a housing having a bottom wall and opposite left and right side walls; a heat sink disposed within the housing, having a base and a plurality of heat sinks extending upwardly from the base, each A core chamber is defined between two adjacent heat sinks; a plurality of battery cells, each battery core is disposed in a core chamber of the heat sink, and two sides of the battery core respectively define heat dissipation of the core chamber a self-adjusting device having a fixing plate supported on a left side wall or a right side wall of the outer casing, a movable plate facing the fixing plate and supported on a left side heat sink or a right side heat sink of the heat sink, and plural The elastic member is clamped between the fixed plate and the movable plate to be tensioned to apply pressure to the battery core sandwiched between the two heat sinks through the movable plate, thereby stabilizing and limiting The rate of change of expansion of the battery cell. The lithium battery module of claim 1, further comprising a cooling system including a bottom having a flow path sandwiched between the bottom wall of the outer casing and the base of the heat sink A cover, a water pump that drives the cooling water to circulate in the flow path to absorb heat, and a device that exchanges the cooling water with the external environment. The lithium battery module according to claim 1, wherein a lower portion of the heat sink forms a buffer angle. The lithium battery module according to claim 1, wherein the self The fixing plate of the adjusting device comprises a plurality of guiding sleeves, each guiding sleeve is composed of two concentric inner guiding sleeves and outer guiding sleeves, and an annular gap is defined between the inner and outer guiding sleeves; the movable plate has a plurality of sleeves Each sleeve is sleeved into a gap of the guide sleeve to press the elastic member disposed in the gap to cause the elastic member to be tensioned. The lithium battery module of claim 1, wherein the fixing plate of the self-adjusting device comprises a plurality of guiding sleeves, the movable plate has a plurality of sleeves, each sleeve is sleeved on the outer circumference of the guiding sleeve to press The elastic member around the guide sleeve is sleeved to tension the elastic member. The lithium battery module according to claim 1, wherein the fixing plate of the self-adjusting device comprises a plurality of guiding sleeves, the movable plate has a plurality of sleeves, and each sleeve is sleeved into a guiding sleeve to be pressed and placed The elastic member in each of the guide sleeves causes the elastic member to be in a tensioned state. The lithium battery module according to any one of claims 4 to 6, wherein the elastic member is a compression spring or a tubular superior glue.