Liquid injection hole structure of battery cover plate and power battery
By installing a diverter and a deflector under the injection hole of the battery cover plate, and using a U-shaped communication channel and vortex dispersion method, the problems of material dropping, insufficient infiltration, serious spike drops and discharges in the prior art are solved, and more efficient electrolyte infiltration and safer liquid injection process are achieved.
Patent Information
- Application Number
- CN202421660127.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-15
- Publication Date
- 2025-05-20
- Estimated Expiration
- 2034-07-15
AI Technical Summary
The existing battery cover liquid injection hole structure has problems such as the electrode sheet dropping, insufficient infiltration of electrolyte, loss of sealing glue nails into the inside of the battery, difficulty in injection of liquid, and serious leakage.
A liquid injection hole structure of a battery cover is designed, using a combination of a diverter and a deflector. The electrolyte is evenly distributed through the U-shaped communication channel and the vortex dispersion method to avoid direct impact on the electrode group. The design of the deflector and the diverter prevents the glue nails from falling and the electrolyte overflowing.
It effectively avoids material dropping of the electrode sheet and damage to the battery cell, increases the contact area between the electrolyte and the electrode group, shortens the infiltration time, prevents the sealing nail from falling in, and improves the liquid level line of the electrolyte inside the battery, reducing the probability of liquid injection and discharge.
Smart Images
Figure CN222887912U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of lithium ion batteries, and particularly relates to a liquid injection hole structure of a battery cover plate and a power battery. Background Art
[0002] There is a plastic part directly below the liquid injection hole of the existing aluminum shell battery cover plate. This plastic part plays a role in protecting the liquid injection hole and supporting the electrode group, preventing the electrode sheet from contacting the cover plate and causing battery short circuit and fire problems. The plastic part directly below the traditional liquid injection hole is basically designed in a direct through-hole or semi-through way, and there are mainly the following deficiencies: First, when injecting liquid, the electrolyte is injected into the battery interior under the action of pressure difference and gravity. Since the battery liquid injection hole is relatively small and the pressure during liquid injection is large, directly impacting the lower electrode group easily causes the electrode sheet to drop material and damage the battery core. Second, during the liquid injection process, the electrolyte is concentrated below the liquid injection hole, and the contact with the electrode group is not sufficient, resulting in a long infiltration time. This structure has no function of electrolyte drainage and dispersion. Third, once the equipment is abnormal after injecting the sealing glue nail, the glue nail is very easy to fall into the battery interior and cause foreign matter inclusion. Fourth, currently in the industry, in order to improve the power density and energy density, when designing the battery, the electrode sheet is highly compacted and the free space is small, resulting in difficult battery liquid injection and serious liquid overflow. Summary of the Utility Model
[0003] The purpose of the utility model is to provide a liquid injection hole structure of a battery cover plate and a power battery to solve the technical problems existing in the prior art.
[0004] To achieve the above purpose, the utility model provides the following technical solution: A liquid injection hole structure of a battery cover plate, including a negative electrode column, a positive electrode column, an explosion-proof valve, a liquid injection hole, a first lower plastic part, a second lower plastic part, and a cover plate. The first lower plastic part and the second lower plastic part are respectively fixed at the bottom of the cover plate. The positive electrode column and the negative electrode column are respectively fixed on the cover plate. The explosion-proof valve is installed on the cover plate. The cover plate is provided with the liquid injection hole. A shunt device is installed below the liquid injection hole. A U-shaped communication channel is formed between the liquid injection hole and the shunt device. When injecting liquid, the electrolyte passes through the liquid injection hole under the action of gravity and differential pressure, and then passes through the shunt device and is evenly distributed and sprinkled on the battery shell wall and the cover plate, without directly impacting the electrode group. A shunt device is provided below the liquid injection hole of this device. By using the principle of U-shaped communicating vessels and the method of eddy current dispersion, the dispersion effect of the electrolyte can be greatly enhanced, the infiltration speed of the electrolyte can be increased, and at the same time, the difficult problem of secondary liquid injection and liquid overflow can be improved.
[0005] Preferably, the diverter is composed of a diversion cover, a support ring and diversion vanes. The support ring is located in the middle of the diversion cover. The circumferential of the support ring is connected to the diversion cover through the diversion vanes. The support ring and the diversion vanes are suspended in the diversion cover, leaving a channel with the bottom of the diversion cover. When the battery is filled with liquid, the electrolyte flows in from the liquid injection hole under the action of gravity and air pressure difference, enters the inside of the diversion cover through the support ring of the diverter, and is diverted upward from the bottom of the diversion cover through the diversion vanes, and is rectified and dispersed evenly into the battery interior, without directly vertically impacting the electrode group and causing damage to the electrode sheets.
[0006] Preferably, a flow guide plate is fixed on one side below the liquid injection hole, and one side of the flow guide plate is bent downward. The bending angle is greater than 120°, and it can be 130°, 140° or 160°. The setting of the flow guide plate can make the electrolyte impact the inside of the battery case, avoiding the plastic parts on one side from being impacted.
[0007] Preferably, the flow guide plate is fixed below the cover plate by riveting. Specifically, a number of grooves are opened below the cover plate, and the upper part of the flow guide plate is provided with rivets corresponding to the grooves, and the rivets are clamped in the grooves to fix the flow guide plate below the cover plate.
[0008] Preferably, the plane where the upper opening of the diversion cover is located is higher than the lower end of the liquid injection hole. Only when the liquid level line is higher than the plane where the upper opening of the diversion cover is located can there be a possibility of overflow. Compared with the traditional structure, the battery interior can hold an additional volume of electrolyte corresponding to a height difference, greatly reducing the probability of liquid injection overflow and improving the phenomena of liquid overflow and liquid spraying.
[0009] Preferably, the diverter and the flow guide plate are of a split structure. The flow guide plate is provided with a connecting sleeve with the same aperture as the liquid injection hole, and the support ring of the diverter is sleeved on the connecting sleeve by interference fit. The split structure can facilitate the replacement of different models of diverters, and only the diverter needs to be replaced separately.
[0010] Preferably, the flow guide plate and the diverter are of an integrally cast structure. The support ring of the diverter is sleeved on the liquid injection hole and integrally cast with the flow guide plate. The advantage of the integrally cast structure is that only by directly installing the flow guide plate, the diverter can be installed together, and the assembly is convenient.
[0011] Preferably, the bottom of the diversion cover is provided with a circular bump. The height of the vertex position of the bump from the lower edge of the liquid injection hole is less than the height of the sealing rubber nail, which plays the role of preventing the rubber nail from falling off by the sealing rubber nail. The bump is directly below the liquid injection hole and also plays the role of electrolyte diversion.
[0012] Preferably, the distance from the cover plate to the bottom of the diverter is less than or equal to the distance from the cover plate to the bottom of the plastic part.
[0013] The present utility model also discloses a power battery, including the liquid injection hole structure of the battery cover plate described above.
[0014] The beneficial effects of the present utility model are as follows: (1) When injecting liquid, the electrolyte is not directly impacted on the lower electrode group under the action of pressure difference and gravity, which will not cause the electrode sheet to drop material and damage the battery core; (2) This structure can divert and disperse the electrolyte, improve the contact area between the electrolyte and the electrode group, and improve the infiltration speed; (3) This structure can support the rubber nails and prevent the rubber nails from falling into the battery interior to cause foreign matter inclusion; (4) This structure can increase the liquid level line of the electrolyte inside the battery and improve the problem of electrolyte overflow. Description of the Drawings
[0015] Figure 1 It is a perspective view in the top view direction of this embodiment;
[0016] Figure 2 It is a perspective view in the bottom view direction of this embodiment;
[0017] Figure 3 It is a three-dimensional sectional view of this embodiment;
[0018] Figure 4 It is a perspective view of the diverter in this embodiment;
[0019] Figure 5 It is a flow state diagram of the electrolyte in this embodiment;
[0020] Figure 6 It is a structural diagram in which the diverter and the diversion plate are separate in this embodiment;
[0021] In the figure, 1 is the negative electrode post; 2 is the positive electrode post; 3 is the explosion-proof valve; 4 is the liquid injection hole; 5 is the first lower plastic part; 6 is the second lower plastic part; 7 is the diversion plate; 71 is the connecting sleeve; 8 is the diverter; 81 is the diversion cover; 82 is the support ring; 83 is the diversion blade; 9 is the circular bump; 10 is the liquid level line; 11 is the cover plate; 12 is the U-shaped communication channel. Specific Embodiment
[0022] The specific embodiment of the present utility model will be described in detail below in conjunction with the drawings and the preferred embodiment.
[0023] As Figure 1-2 shown, a liquid injection hole structure of a battery cover plate includes a negative electrode post 1, a positive electrode post 2, an explosion-proof valve 3, a liquid injection hole 4, a first lower plastic part 5, a second lower plastic part 6 and a cover plate 11. The first lower plastic part and the second lower plastic part are respectively fixed at the bottom of the cover plate. The positive electrode post and the negative electrode post are respectively fixed on the cover plate. The explosion-proof valve is installed on the cover plate. The cover plate is provided with the liquid injection hole 4, providing space for subsequent welding and sealing of the aluminum nail, and designed as a countersunk groove.
[0024] AsFigure 3 and Figure 4 As shown in Figure 4 , as an improvement of the present utility model, a shunt 8 is installed below the liquid injection hole, and a U-shaped communication channel 12 is formed between the liquid injection hole and the shunt ( Figure 5 in the direction of the arrow in Figure 5 ). When injecting liquid, the electrolyte passes through the liquid injection hole under the action of gravity and differential pressure, and then passes through the shunt and is evenly sprinkled on the battery case wall and the cover plate, without directly impacting the electrode group. This device is provided with a shunt below the liquid injection hole. By applying the principle of U-shaped communicating vessels and the method of vortex dispersion, the dispersion effect of the electrolyte can be greatly increased, the infiltration speed of the electrolyte can be improved, and at the same time, the difficult problem of liquid overflow during secondary liquid injection can be improved.
[0025] Specifically, as shown in Figure 4 Figure 4 , the shunt 8 is composed of a shunt cover 81, a support ring 82 and shunt blades 83. The support ring is located in the middle of the shunt cover, and the circumference of the support ring is connected to the shunt cover through the shunt blades. The support ring and the shunt blades are suspended in the shunt cover, leaving a channel with the bottom of the shunt cover. When injecting liquid into the battery, the electrolyte flows in from the liquid injection hole under the action of gravity and air pressure difference, enters the inside of the shunt cover through the support ring of the shunt, and is shunted upward from the bottom of the shunt cover through the shunt blades. The electrolyte is evenly dispersed and injected into the battery interior, without directly vertically impacting the electrode group, and will not cause damage to the electrode plates. Further, the axial inclination angle of the shunt blades relative to the axis of the support ring is 0 - 60°. It can be specifically designed according to requirements. In this embodiment, six shunt blades are adopted, and the inclination directions of the blades are the same, so as to evenly disperse the electrolyte to the surrounding, better "bathe" the electrode group, fully contact the electrode plates, improve the infiltration effect, and increase the diffusion speed.
[0026] Further, in order to shunt the electrolyte and prevent the glue nails from falling off, as shown in Figure 5 Figure 5 , a circular bump 9 is provided at the bottom of the shunt cover. The height of the vertex of this circular bump from the lower edge of the liquid injection hole is less than the height of the sealing glue nail, which plays a role in preventing the glue nails from falling off. Even if the glue nails are inserted deeper, they will not fall into the battery interior and cause internal foreign objects to scratch the electrode group. This structure improves the battery safety. This circular bump is located directly below the liquid injection hole and also plays a role in shunting the electrolyte. After the electrolyte enters the shunt, it is evenly dispersed to the surrounding through the circular bump, and then rectified and accelerated by the shunt blades and dispersed onto the battery cover plate and the aluminum shell wall, and is evenly sprayed on the electrode group through multiple reflections and the diversion of the diversion plate. The electrolyte not only infiltrates the electrode group from top to bottom, but also can diffuse and infiltrate the electrode group from bottom to top through capillary action, greatly increasing the contact area, improving the infiltration speed, and improving the infiltration effect.
[0027] Further, as shown in Figure 3As shown in the figure, in order to prevent the electrolyte from impacting the plastic parts, a flow guide plate 7 is provided on one side below the liquid injection hole. The flow guide plate is fixed below the cover plate by riveting. Specifically, several grooves are opened below the cover plate, and the upper part of the flow guide plate is provided with rivets corresponding to the grooves. The rivets are clamped into the grooves to fix the flow guide plate below the cover plate. One side of the flow guide plate is bent downward, and the bending angle ≥ 120° can be 130°, 140° or 160°, etc. The setting of the flow guide plate can make the electrolyte impact the inside of the battery case, avoiding impacting the plastic parts on one side. This structure can also prevent the electrolyte from flowing back due to high-pressure impact of the electrolyte, affecting the liquid injection effect.
[0028] Furthermore, the flow guide plate and the shunt can also be an integrally cast structure, such as Figure 3 and Figure 5 shown. The support ring 82 in the shunt is integrally cast and formed with the flow guide plate. The advantage of using an integrally cast structure is that only by directly installing the flow guide plate, the shunt can be installed together, and the assembly is convenient.
[0029] In addition, the shunt and the flow guide plate can also be a split structure. Specifically, as Figure 6 shown, a connecting sleeve 71 with the same aperture as the liquid injection hole is provided on the flow guide plate 7, and the support ring 82 of the shunt is sleeved on the connecting sleeve by interference fit. The use of a split structure can facilitate the replacement of shunts of different models, and only the shunt needs to be replaced separately.
[0030] Furthermore, as Figure 5 shown, the plane where the upper opening of the shunt cover is located is higher than the lower end of the liquid injection hole. The advantage of this design is that it can raise the liquid level line 10 of the internal electrolyte, and to a certain extent, reduce the problem of electrolyte overflow. Only when the liquid level line 10 is higher than the plane where the upper opening of the shunt cover is located, the electrolyte may overflow, greatly reducing the probability of liquid injection overflow and improving the overflow and spraying phenomenon.
[0031] The present utility model also discloses a power battery, including the liquid injection hole structure of the battery cover plate. By adding a shunt below the liquid injection hole of the traditional power battery, the structure is simple and convenient to use. Using the principle of U-shaped communicating vessels and the method of vortex dispersion can greatly increase the effect of electrolyte dispersion, improve the electrolyte infiltration speed, and at the same time solve the difficult problem of secondary liquid injection overflow of the power battery.
[0032] For those of ordinary skill in the art, without departing from the principle of the present utility model, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present utility model.
Claims
1. A liquid injection hole structure of a battery cover, comprising a negative pole, a positive pole, an explosion-proof valve, a liquid injection hole, a first lower plastic part, a second lower plastic part and a cover, wherein the first lower plastic part and the second lower plastic part are respectively fixed to the bottom of the cover, the positive pole and the negative pole are respectively fixed to the cover, the explosion-proof valve is mounted on the cover, and the cover is provided with the liquid injection hole, characterized in that: A diverter is installed below the injection hole, and a U-shaped connecting channel is formed between the injection hole and the diverter. During injection, the electrolyte passes through the injection hole under the influence of gravity and differential pressure, and then passes through the diverter and is evenly distributed on the battery shell wall and the cover plate without directly impacting the electrode group.
2. The liquid injection hole structure of the battery cover according to claim 1, characterized in that: The splitter consists of a splitter cover, a support ring and splitter blades. The support ring is located in the middle of the splitter cover. The circumference of the support ring is connected to the splitter cover through the splitter blades. The support ring and the splitter blades are suspended in the splitter cover, leaving a channel with the bottom of the splitter cover.
3. The liquid injection hole structure of the battery cover according to claim 2, characterized in that: A guide plate is fixed on one side below the injection hole, and one side of the guide plate is bent downward.
4. The liquid injection hole structure of the battery cover according to claim 3, characterized in that: The guide plate is fixed below the cover plate by riveting.
5. The liquid injection hole structure of the battery cover according to claim 2, characterized in that: The plane where the upper opening of the diverter cover is located is higher than the lower end of the liquid injection hole.
6. The liquid injection hole structure of the battery cover according to claim 4, characterized in that: The diverter and the guide plate are split structures. The guide plate is provided with a connecting sleeve with the same aperture as the injection hole. The supporting ring of the diverter is sleeved on the connecting sleeve by interference fit.
7. The liquid injection hole structure of the battery cover according to claim 6, characterized in that: The guide plate and the diverter are an integrally cast structure, and the support ring of the diverter is sleeved on the injection hole and is integrally cast with the guide plate.
8. The liquid injection hole structure of the battery cover according to claim 2, characterized in that: The bottom of the flow divider is provided with a circular convex point.
9. The liquid injection hole structure of the battery cover according to claim 2, characterized in that: The distance from the cover plate to the bottom of the diverter is less than or equal to the distance from the cover plate to the bottom of the plastic part.
10. A power battery, characterized in that: A liquid injection hole structure comprising a battery cover plate as described in any one of claims 1-9.