阅读说明：本技术 一种锂电池防爆阀防腐蚀结构 (Lithium cell explosion-proof valve anticorrosion structure ) 是由 周步清 余志刚 黄明 张元春 张仁柏 娄忠良 于 2021-10-18 设计创作，主要内容包括：一种锂电池防爆阀防腐蚀结构,基板上设置有储液槽,注液口设置在储液槽的底部,防爆阀周围设置有凹槽,凹槽与注液口通过疏导槽连通,凹槽内积聚的电解液通过疏导槽流向储液槽内。本发明结构简单,工艺流程易于操作,电池注液时电解液滴落或残留到基板表面,由于涂层的不粘型和低摩擦系数,液珠会向低处汇集至储液槽,被储液槽内的吸附纸吸附；待注液口密封后,在清洗工序取出吸附纸并对电池表面进行清洁,保证电解液不会残留到电池表面,避免电解液腐蚀。(The utility model provides an explosion-proof valve anticorrosion structure of lithium cell, is provided with the reservoir on the base plate, annotates the liquid mouth and sets up in the bottom of reservoir, is provided with the recess around the explosion-proof valve, and the recess communicates through dredging the groove with annotating the liquid mouth, and the electrolyte of gathering in the recess is through dredging the groove flow in to the reservoir. The invention has simple structure and easy operation of the process flow, the electrolyte drops or remains on the surface of the substrate when the battery is injected, and liquid beads can be converged to the liquid storage tank to be adsorbed by the adsorption paper in the liquid storage tank due to the non-stick type and the low friction coefficient of the coating; after the liquid injection port is sealed, the adsorption paper is taken out in the cleaning process and the surface of the battery is cleaned, so that the electrolyte is prevented from remaining on the surface of the battery, and the electrolyte is prevented from being corroded.)

1. The utility model provides a lithium cell explosion-proof valve anticorrosion structure which characterized in that:

the liquid storage tank (3) is arranged on the substrate (1), the liquid injection port (4) is arranged at the bottom of the liquid storage tank (3), the groove (5) is arranged around the anti-explosion valve (2), the groove (5) is communicated with the liquid injection port (4) through the dredging guide groove (6), and electrolyte accumulated in the groove (5) flows into the liquid storage tank (3) through the dredging guide groove (6).

2. The lithium battery explosion-proof valve corrosion prevention structure of claim 1, wherein:

the area of the vacuum suction nozzle is reserved around the liquid injection port (4) as a plane;

the side wall of the liquid storage tank (3) is provided with a slope, and the slope is towards the liquid injection port (4) at the bottom.

3. The lithium battery explosion-proof valve corrosion prevention structure of claim 1, wherein:

the bottom of the groove (5) is also arranged to be slope-shaped and is inclined towards the dredging groove (6).

4. The lithium battery explosion-proof valve corrosion prevention structure of claim 1, wherein:

the surface areas of the groove and the cover plate of the explosion-proof valve are sprayed with low-friction-coefficient corrosion-resistant coatings.

5. The lithium battery explosion-proof valve corrosion prevention structure of claim 1, wherein:

and adsorption paper for adsorbing electrolyte is attached to the liquid storage tank (3).

6. The lithium battery explosion-proof valve corrosion prevention structure of claim 1, wherein:

and a protective film is attached to the edge of the explosion-proof valve (2).

Technical Field

The invention relates to the field of lithium battery explosion-proof valves, in particular to an anti-corrosion structure of a lithium battery explosion-proof valve.

Background

With the rapid development of new energy industry, the application field of the lithium ion battery is wider, the electrolyte commonly used by the lithium ion battery at present contains lithium hexafluorophosphate and an additive, and the lithium hexafluorophosphate and the additive react to form hydrofluoric acid after contacting with moisture in the air, so that the lithium hexafluorophosphate and the additive have certain corrosivity; in addition, on the square aluminum-shell battery, because the position of the liquid injection port is close to that of the explosion-proof valve, the injection of the electrolyte is easy to expose, so that the explosion-proof valve is corroded, the bearing pressure of the explosion-proof valve cannot meet the design requirement, and the safety problem caused by battery failure is caused.

Disclosure of Invention

The invention provides a corrosion-proof structure of an explosion-proof valve of a lithium battery to solve the problems in the prior art, and the invention is further explained below.

The utility model provides an explosion-proof valve anticorrosion structure of lithium cell, is provided with the reservoir on the base plate, annotates the liquid mouth and sets up in the bottom of reservoir, is provided with the recess around the explosion-proof valve, and the recess communicates through dredging the groove with annotating the liquid mouth, and the electrolyte of gathering in the recess is through dredging the groove flow in to the reservoir.

Preferably, the area of the vacuum suction nozzle is reserved around the liquid injection port as a plane, the side wall of the liquid storage tank is provided with a slope, and the slope is towards the liquid injection port at the bottom, so that the electrolyte on the surface of the cover plate is guided to the liquid injection port to be gathered together.

Preferably, the bottom of the groove is also provided with a slope, and the slope is towards the dredging groove, so that the electrolyte can automatically flow into the liquid storage tank.

Preferably, a low-friction-coefficient corrosion-resistant coating is sprayed on the surface areas of the groove and the cover plate of the explosion-proof valve so as to reduce the adhesion of the electrolyte and facilitate the flow collection of the electrolyte.

Preferably, the liquid storage tank is attached with adsorption paper with strong electrolyte adsorption capacity, so that the electrolyte is convenient to adsorb and fix, and the cleaning and the replacement are easier.

Preferably, a protective film is attached to the edge of the explosion-proof valve, double protection is formed by matching with the groove to block a channel of electrolyte flowing to the explosion-proof valve, double-sided adhesive tape is arranged on the back of the edge of the protective film, and a dispensing mode is adopted in the middle of the protective film, so that the explosion-proof valve is communicated with the outside to facilitate air exhaust, and the explosion-proof function is maintained.

Has the advantages that: compared with the prior art, the invention has simple structure and easy operation of the process flow, the electrolyte drops or remains on the surface of the substrate when the battery is injected, and liquid beads can be converged to the liquid storage tank at a lower part and absorbed by the absorption paper in the liquid storage tank due to the non-stick type and the low friction coefficient of the coating; after the liquid injection port is sealed, the adsorption paper is taken out in the cleaning process and the surface of the battery is cleaned, so that the electrolyte is prevented from remaining on the surface of the battery, and the electrolyte is prevented from being corroded.

Drawings

FIG. 1: a schematic structural diagram of one embodiment of the present invention;

FIG. 2: a top view of another embodiment of the present invention;

in the figure: the device comprises a base plate 1, an explosion-proof valve 2, a liquid storage tank 3, a liquid injection port 4, a groove 5, a dredging guide groove 6, a corrosion-resistant coating 7, adsorption paper 8 and a protective film 9.

Detailed Description

A specific embodiment of the present invention will be described in detail with reference to fig. 1-2.

In the prior lithium battery, an explosion-proof valve 2 is arranged on a substrate 1 for safety, when the internal pressure of a battery pack box body is smaller than the set explosion value of the explosion-proof valve, the battery pack box body belongs to a normal working state, gas inside and outside the cavity freely circulates through the explosion-proof valve 2, the gas flows from the side with high pressure to the side with low pressure, namely when the internal pressure of the cavity is larger than the external pressure of the cavity, the gas is discharged outwards, and when the internal pressure of the cavity is smaller than the external pressure of the cavity, the gas enters an inner cavity, so that the balance of internal and external air pressure is realized, and in this state, the PUW explosion-proof valve plays the role of a waterproof ventilation valve; when the pressure intensity in the cavity is larger than or equal to the set explosion value of the explosion-proof valve, the explosion-proof working state is adopted, the internal pressure jacks the built-in piston body, gas is directly communicated with the outside through the barrier-free channel, and the gas is rapidly discharged, so that the pressure in the cavity is rapidly reduced, the cavity is prevented from being exploded, and the explosion-proof function is realized in the state.

The electrolyte is sprayed onto the explosion-proof valve or flows onto the explosion-proof valve based on the flowing randomness, so that the explosion-proof valve is corroded, the bearing pressure of the explosion-proof valve cannot meet the design requirement, and the safety problem caused by battery failure is caused.

Based on this, the invention provides an anti-corrosion structure of an explosion-proof valve of a lithium battery, which avoids the existing disadvantages, specifically, in the embodiment, the substrate 1 is provided with the liquid storage tank 3, the liquid injection port 4 is arranged at the bottom of the liquid storage tank 3, and when liquid is injected, even if the electrolyte is exposed, the electrolyte is collected in the liquid storage tank 3 and does not flow randomly, so that the electrolyte is prevented from flowing to the explosion-proof valve 2.

In this embodiment, in order to enlarge the collection area of the reservoir 3 to increase the collection area of the externally discharged electrolyte, the area of the vacuum suction nozzle is reserved around the liquid injection port as a plane, the side wall of the reservoir 3 is set to be a slope, and the slope is toward the liquid injection port 4 at the bottom, so as to collect the electrolyte on the surface of the cover plate together at the liquid injection port.

In practice, based on the trend that the spatial layout is more and more compact, the distance between the explosion-proof valve and the liquid injection port cannot reach the complete safety distance, the electrolyte which splashes when the liquid is injected cannot be completely avoided, namely, the probability of the electrolyte falling on the explosion-proof valve is inevitable, in view of the above, the groove 5 is arranged around the explosion-proof valve in the embodiment, the explosion-proof valve is separated from the liquid injection port by the groove 5, and the electrolyte is collected in the groove 5 in the process of flowing to the explosion-proof valve.

Recess 5 and notes liquid mouth 4 are through dredging guide slot 6 intercommunication, and the electrolyte that gathers in the recess 5 flows to the reservoir 3 in through dredging guide slot 6, and further, for avoiding dredging to have the electrolyte that is detained and gathers in the groove, recess 5 bottom also sets up to slope form, and the slope is to dredging guide slot 6 department, and the electrolyte of being convenient for flows automatically and gets into in the reservoir.

In another embodiment, on the basis of the above embodiment, the low-friction-coefficient corrosion-resistant coating 7 is sprayed on the surface areas of the explosion-proof valve groove and the cover plate so as to reduce the adhesion of the electrolyte and facilitate the flow collection of the electrolyte.

The liquid storage tank 3 is attached with adsorption paper 8 with strong electrolyte adsorption capacity, so that the electrolyte is convenient to adsorb and fix, and the cleaning and the replacement are easier.

Attached protection film 9 in explosion-proof valve edge, cooperation recess form dual protection in order to block the passageway of electrolyte flow direction explosion-proof valve, protection film edge back of the body double faced adhesive tape, the mode is glued to the centre adoption point, makes explosion-proof valve and external world link up and do benefit to the exhaust, maintains explosion-proof function.

The invention has simple process and controllable cost, and the specific process is as follows:

when the substrate is stamped, an annular groove with the thickness of 0.2-1 mm is stamped at the peripheral position of the explosion-proof valve hole, and a slope and a liquid storage tank are stamped on the outer ring of the liquid injection hole; after the substrate is stamped, spraying a low-friction-coefficient corrosion-resistant coating on the surface of the cover plate, wherein the coating is made of polytetrafluoroethylene or temperature-resistant polymer grafted wax (such as PE wax, PP wax and the like), the thickness of the coating is controlled to be 30-70 microns, and a protective isolation layer is formed on the surface of the cover plate; in the middle area of the explosion-proof valve hole and the groove, dispensing fluororubber (without limitation) by using a dispenser; simultaneously, an annular double-sided adhesive tape is arranged on the periphery back of the anti-explosion valve protection film, and the upper end of the anti-explosion valve hole is covered by the double-sided adhesive tape to form a first layer of electrolyte protection ring; an annular groove at the periphery of the explosion-proof valve hole forms a second layer of protective ring; at the moment, the periphery and the upper part of the explosion-proof valve form a state of being completely isolated from the outside, so that the explosion-proof valve is effectively protected; meanwhile, the fluororubber in the middle area is in a dotted form, so that the inner ring of the protective film cannot be completely sealed to provide an exhaust channel for the explosion of the explosion-proof valve, and the accuracy in pressure testing is ensured.

When the battery is injected with liquid, the electrolyte drops or remains on the surface of the substrate, and due to the non-stick property and low friction coefficient of the coating, liquid beads are collected to a liquid storage tank from a low position and are adsorbed by adsorption paper in the liquid storage tank; after the liquid injection port is sealed, the adsorption paper is taken out in the cleaning process and the surface of the battery is cleaned, so that the electrolyte is prevented from remaining on the surface of the battery, and the electrolyte is prevented from being corroded.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.