CN107342433A - Lithium battery - Google Patents

Abstract

The invention provides a lithium battery, wherein two wiring components are arranged on a shell, a plurality of alternately stacked positive electrode plates and negative electrode plates are accommodated in the shell, a flaky solid molecular polyelectrolyte is clamped between any positive electrode plate and an adjacent negative electrode plate, and the positive surface and the negative surface of the flaky solid molecular polyelectrolyte are respectively attached to the positive coating of the adjacent positive electrode plate and the negative coating of the negative electrode plate. And a plurality of positive electrode tabs of the plurality of positive electrode plates are electrically connected with one wiring assembly, and a plurality of negative electrode tabs of the plurality of negative electrode plates are electrically connected with the other wiring assembly. Therefore, the battery can normally operate in high and low temperature environments through the characteristics of the solid-state molecular polyelectrolyte coating, and the performance of the battery is stable, so that the use safety is ensured.

Description

lithium battery

technical field

The invention relates to a lithium battery, especially a lithium battery that can operate stably in high and low temperature environments, and can be used for charging and discharging at high rates and high currents to ensure safe use.

Background technique

Generally, the manufacturing process of electrode sheets in lithium batteries can be roughly divided into two methods: stacking and winding. Both methods are formed by sandwiching separator paper between the positive electrode and negative electrode, and then repeatedly stacking or winding. After entering the case, inject electrolyte, and finally seal with steel balls to form a lithium battery. However, when the battery core is in the state of charge and discharge, short circuit or high temperature environment, the temperature of the battery fluid rises to a high temperature of about 75-80°C, because the separator paper and the electrolyte are not resistant to high and low temperatures, therefore, Not only is it easy to cause gas swelling and liquid leakage, but also cause the performance of the battery cell to decline, and even cause an explosion, which raises safety concerns.

Furthermore, currently used lithium batteries mainly contain an electrolyte solution and a lithium battery winding core inside the casing, and the lithium battery winding core is formed by continuously winding a positive electrode sheet, a separator, and a negative electrode sheet. Wherein, the positive electrode tab is welded to the positive electrode lug, and the positive electrode lug is welded on the inner wall of the casing, so that the casing is electrically connected to the positive electrode terminal. The negative pole piece is welded to the negative pole tab, and the negative pole tab is welded upward to the bottom of the negative pole terminal of the casing. In this way, a nut can be threaded through the external thread on the top of the positive terminal and the top of the negative terminal, respectively, and different terminals can be respectively fixed to output positive and negative electricity respectively.

However, the above-mentioned negative pole lug is drawn out from the negative pole piece, and then welded on the bottom of the negative pole terminal. The quality is not easy to control, and it is often in point-like contact. Therefore, it is easy to cause poor conduction and heat dissipation. It is only suitable for low-current energy storage and power consumption, and is not suitable for high-rate and high-current charging and discharging.

Contents of the invention

In view of this, in order to provide a structure different from the prior art and to improve the above-mentioned shortcomings, the inventor has accumulated many years of experience and continuous research and development, so the present invention is produced.

An object of the present invention is to provide a lithium battery, through a kind of cross-stacking of a plurality of positive electrode sheets and a plurality of negative electrode sheets, and the positive electrode coating of the adjacent positive electrode sheet and the negative electrode coating of the negative electrode sheet A sheet-like solid molecular polyelectrolyte structure is sandwiched between them, so as to solve the problem that the separator paper and electrolyte of the existing lithium battery are not resistant to high and low temperatures, and are prone to gas swelling and leakage, and can make the performance stable. And ensure safe use.

An object of the present invention is to provide a lithium battery, by forming a negative electrode tab group and a positive electrode tab group on both sides of a plurality of positive and negative electrode sheets stacked crosswise, and making the negative electrode conductive sheet and the positive electrode conductive sheet respectively large The area method forms an electrical connection structure with the negative electrode tab group and the positive electrode tab group, so as to solve the problem that the welding point of the existing lithium battery is point contact, its quality is not easy to control, conduction and heat dissipation are poor, and it is only suitable for small current storage. It can effectively conduct electricity and dissipate heat, and meet the needs of high-rate and high-current charging and discharging.

In order to achieve the above-mentioned purpose, the lithium battery provided by the present invention comprises a casing, the casing is provided with a first wiring assembly and a second wiring assembly, and a plurality of positive electrode sheets and a plurality of negative electrode sheets are housed in the casing, and the positive electrode sheet Most of the areas on the front and back sides of the negative electrode sheet are respectively combined with a positive coating to form a positive tab, and most of the areas on the front and back sides of the negative electrode sheet are respectively combined with a negative coating to form a negative tab. A positive pole tab is electrically connected to the first wiring assembly, and a plurality of negative pole tabs is electrically connected to the second wiring assembly. Its main technical features are: a plurality of positive electrode sheets and a plurality of negative electrode sheets are stacked crosswise, A sheet-shaped solid molecular polyelectrolyte is sandwiched between any positive electrode sheet and an adjacent negative electrode sheet, and the front and back sides of the sheet-shaped solid molecular polyelectrolyte are respectively attached to the positive electrode of the adjacent positive electrode sheet. Coating and negative electrode coating of the negative electrode sheet.

During implementation, the present invention also includes a positive electrode conductive sheet and a negative electrode conductive sheet, the casing includes a lower casing and a cover plate that covers the top of the lower casing, and the first wiring assembly and the second wiring assembly are connected to the cover plate; The positive conductive piece is combined at the bottom of the first wiring assembly and extends downward away from the cover plate, the negative conductive piece is combined at the bottom of the second wiring component and extends downward away from the cover plate; and a plurality of positive electrodes A plurality of positive tabs of the electrode sheet form a positive tab group, a plurality of negative tabs of a plurality of negative electrode sheets form a negative tab group, the positive tab group and the negative tab group are arranged in an upright shape, and the positive The pole ear group and the negative pole ear group are reversely arranged on both sides of the combined plurality of positive electrode sheets and the plurality of negative electrode sheets; the positive electrode ear group is electrically connected to the positive electrode conductive sheet, and the negative electrode ear group is electrically connected to the negative electrode. The sheets are electrically connected.

During implementation, the above-mentioned positive electrode conductive sheet includes a first positioning portion and a first extension portion, the first positioning portion is combined with the bottom of the first wiring assembly to be electrically connected, and the first extension portion is formed by one side of the first positioning portion Extending downward in a direction approximately perpendicular to the first positioning portion; and the negative electrode conductive sheet includes a second positioning portion and a second extending portion, the second positioning portion is combined with the bottom of the second wiring assembly to be electrically connected, the second The two extension parts extend downward from one side of the second positioning part in a direction roughly perpendicular to the second positioning part.

During implementation, the first positioning portion and the first extension portion are in an inverted L shape, and the second positioning portion and the second extension portion are in an inverted L shape.

In order to further understand the present invention, preferred embodiments are given below, and with reference to the accompanying drawings and figure numbers, the specific components of the present invention and the effects achieved are described in detail as follows.

Description of drawings

Figure 1 is an exploded view of positive and negative electrode sheets and sheet-like solid molecular polyelectrolytes cross-stacked for a preferred embodiment of the present invention;

Fig. 2 is a perspective view of positive and negative electrode sheets and sheet-like solid molecular polyelectrolytes cross-stacked for a preferred embodiment of the present invention;

Figure 3 is an exploded view of some components of a preferred embodiment of the present invention;

FIG. 4 is an exploded view of components of a preferred embodiment of the present invention.

Explanation of reference signs:

Lithium battery 1; Case 2;

Lower case 21; Cover plate 22;

Top plate 221; Insulation sheet 222;

The first wiring assembly 3; rubber sleeves 31, 41;

The second wiring assembly 4; the positive conductive sheet 5;

the first positioning part 51; the first extending part 52;

Negative electrode conductive sheet 6; Second positioning part 61;

The second extension part 62; the positive electrode sheet 7;

positive electrode coating 71; positive electrode tab 72;

Positive electrode tab group 73; Negative electrode sheet 8;

Negative electrode coating 81; Negative electrode tab 82;

Negative electrode tab group 83; Solid molecular polyelectrolyte 9;

Insulating rubber sleeve 91.

detailed description

The lithium battery of the present invention is provided with two wiring assemblies on a casing, and a plurality of cross-stacked positive and negative electrode sheets are accommodated inside the casing, and any positive electrode sheet is sandwiched between an adjacent negative electrode sheet A sheet-shaped solid molecular polyelectrolyte, the front and back sides of the sheet-shaped solid molecular polyelectrolyte are attached to the positive electrode coating of the adjacent positive electrode sheet and the negative electrode coating of the negative electrode sheet respectively. The plurality of positive tabs of the plurality of positive electrode sheets are electrically connected to a wiring assembly, and the plurality of negative tabs of the plurality of negative electrode sheets are electrically connected to another wiring assembly.

Please refer to FIGS. 1-4, which is a preferred embodiment of the lithium battery 1 of the present invention, including a casing 2, a first wiring assembly 3, a second wiring assembly 4, a positive electrode conductive sheet 5, and a negative electrode. Conductive sheets 6 , a plurality of positive electrode sheets 7 , a plurality of negative electrode sheets 8 and a plurality of sheet-shaped solid molecular polyelectrolytes 9 .

The casing 2 includes a lower casing 21 and a cover plate 22 , the lower casing 21 is a hollow cuboid with an opening at the top, and the cover plate 22 covers the top of the lower casing 21 to close the opening. The cover plate 22 includes a top plate 221 and an insulating sheet 222 , and the top plate 221 and the insulating sheet 222 are stacked up and down. The first wiring assembly 3 and the second wiring assembly 4 respectively pass through two rubber sleeves ( 31 , 41 ) to be connected to the cover plate 22 .

The positive electrode conductive sheet 5 is formed by bending a flat plate, and includes a first positioning portion 51 and a first extending portion 52. The first extending portion 52 is roughly perpendicular to the first positioning portion from one side of the first positioning portion 51. 51 extends downwards, so that the first positioning portion 51 and the first extending portion 52 are roughly in an inverted L shape. The first positioning portion 51 is located below the cover plate 22 , and connects and fixes the first wiring assembly 3 upward by riveting, so that the first positioning portion 51 and the first wiring assembly 3 are electrically connected.

The negative electrode conductive sheet 6 is formed by bending a flat plate, and includes a second positioning portion 61 and a second extending portion 62. The second extending portion 62 is roughly perpendicular to the second positioning portion from one side of the second positioning portion 61. 61 extends downwards, so that the second positioning portion 61 and the second extending portion 62 are roughly in an inverted L shape. The second positioning portion 61 is located below the cover plate 22 , and connects and fixes the second wiring assembly 4 upward by riveting, so that the second positioning portion 61 and the second wiring assembly 4 are electrically connected.

A plurality of positive electrode sheets 7 , a plurality of negative electrode sheets 8 and a plurality of sheet-shaped solid molecular polyelectrolytes 9 are accommodated in the lower casing 21 of the casing 2 . Among them, a plurality of positive electrode sheets 7 and a plurality of negative electrode sheets 8 are cross-stacked, and most of the front and back sides of any positive electrode sheet 7 are respectively combined with a positive electrode coating 71 to form a positive electrode tab 72. Two positive pole tabs 72 are stacked and pressed to form a positive pole tab group 73; most of the front and back sides of any negative electrode sheet 8 are combined with a negative electrode coating 81 to form a negative pole tab 82, a plurality of The negative tabs 82 are stacked and pressed to form a negative tab set 83 . And any sheet-shaped solid molecular polyelectrolyte 9 is sandwiched between any positive electrode sheet 7 and an adjacent negative electrode sheet 8, and the front and back sides of the solid molecular polyelectrolyte 9 are attached to the adjacent electrode sheet 9 respectively. The positive electrode coating 71 of the positive electrode sheet 7 and the negative electrode coating 81 of the negative electrode sheet 8 . During implementation, the sheet-like solid molecular polyelectrolyte 9 is a high-molecular polymer resistant to high and low temperatures, for example: has a repeating unit E represented by the following general formula I:

which the The repeating unit E 1 has two side groups, L 1 and L 2 , bonded to two of the four N atoms of the repeating unit E 1;

L 1 and L 2 independently represent the group R 1-SO3M,

R 1 represents a hydrocarbon;

M represents a cation selected from the group consisting of Li+, Na+, H+ and K+;

R 3 represents a group H or SO3M;

And x represents an integer greater than 10.

When a plurality of positive electrode sheets 7, a plurality of negative electrode sheets 8, and a plurality of sheet-like solid molecular polyelectrolytes 9 are cross-stacked, the positive electrode tab group 73 and the negative electrode tab group 83 are respectively arranged in an upright shape, and the positive electrode tabs The group 73 and the negative tab group 83 are oppositely disposed on both sides of the assembled plurality of positive electrode sheets 7 and the plurality of negative electrode sheets 8 .

During implementation, the first extension portion 52 of the positive electrode conductive sheet 5 extends downward in a direction away from the cover plate 22, and the vertical length of the first extension portion 52 is preferably more than 1/3 of the vertical height of the positive electrode tab group 73. The second extension 62 of the negative electrode conductive sheet 6 extends downward in a direction away from the cover plate 22 , and the vertical length of the second extension 62 is preferably more than 1/3 of the vertical height of the negative electrode tab set 83 . When the first extension portion 52 is connected to the positive tab set 73 by welding, the positive tab set 73 is electrically connected to the first wiring assembly 3 , and when the second extension portion 62 is connected to the negative tab set 83 by welding, The negative tab set 83 is electrically connected to the second wiring assembly 4 .

In addition, the outer periphery of the positive electrode conductive sheet 5, the negative electrode conductive sheet 6, the plurality of positive electrode sheets 7, the plurality of negative electrode sheets 8, and the plurality of sheet-shaped solid molecular polyelectrolytes 9 is covered with an insulating rubber sleeve 91, so as to prevent short circuits. And when above-mentioned each element is housed in the interior of the lower housing 21 of metal material, after the gap between the lower housing 21 and the cover plate 22 is joined, an insulating film is added and coated on the outer periphery of the housing 2 to form One battery1.

Therefore, the present invention has the following advantages:

1. The present invention sandwiches the sheet-like solid molecular polyelectrolyte between the positive and negative electrode sheets to replace the diaphragm paper and electrolyte at the same time. Therefore, it can not only prevent the problems of gas swelling and leakage at high temperature, In order to ensure the safety of use, and can still operate normally in a low temperature environment, so as to effectively improve operating efficiency and reduce manufacturing and assembly costs.

2. The positive and negative conductive sheets of the present invention are electrically connected to the positive tab set and the negative tab set in a large-area manner. Therefore, not only can the conductive voltage and current be stabilized, but also meet the requirements of high-rate and large-current charging and charging. Discharge use requirements, and can effectively dissipate heat to increase product life and ensure safe use.

To sum up, according to the content disclosed above, the present invention can clearly achieve the expected purpose, providing a battery that can not only stabilize the performance of the battery, but also meet the needs of high-rate and high-current charging and discharging, so as to improve the conductivity and Heat dissipation effect, and can ensure the use of safe lithium batteries, which is of great value in industrial utilization, and the invention patent application is filed according to law.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than limiting them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: It is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the various embodiments of the present invention. scope.

Claims (5)

1. A lithium battery comprises a casing, the casing is provided with a first wiring assembly and a second wiring assembly, a plurality of positive electrode sheets and a plurality of negative electrode sheets are housed in the casing, the positive electrode sheet of the positive electrode sheet is Most of the areas on the opposite sides are combined with a positive coating to form a positive tab, and most of the areas on the front and back of the negative electrode sheet are combined with a negative coating to form a negative tab. A positive pole lug is electrically connected to the first wiring assembly, and the plurality of negative pole lugs are electrically connected to the second wiring assembly. The improvement lies in: The plurality of positive electrode sheets and the plurality of negative electrode sheets are cross-stacked, and a sheet-shaped solid molecular polyelectrolyte is sandwiched between any one of the positive electrode sheets and the adjacent negative electrode sheet, and the sheet-shaped The positive and negative surfaces of the solid molecular polyelectrolyte are attached to the positive coating of the adjacent positive electrode sheet and the negative coating of the negative electrode sheet respectively. 2. The lithium battery according to claim 1, further comprising a positive electrode conductive sheet and a negative electrode conductive sheet, the casing includes a lower casing and a cover plate on the top of the lower casing, the first A wiring assembly and the second wiring assembly are connected to the cover plate; the positive conductive piece is combined with the bottom of the first wiring component and extends downward in a direction away from the cover plate; the negative conductive piece is combined with the second wiring component The bottom of the two wiring components, and extend downward away from the cover plate; and the plurality of positive tabs of the plurality of positive electrode sheets form a positive tab group, and the plurality of negative electrodes of the plurality of negative electrode sheets The tabs form a negative tab set, the positive tab set and the negative tab set are arranged in an upright shape, and the positive tab set and the negative tab set are reversely arranged on the combined positive electrodes sheet and both sides of the plurality of negative electrode sheets; the positive tab set is electrically connected to the positive conductive sheet, and the negative tab set is electrically connected to the negative conductive sheet. 3. The lithium battery according to claim 2, wherein the positive conductive sheet includes a first positioning portion and a first extension portion, and the first positioning portion is combined with the bottom of the first wiring assembly so as to present an electric current. Sexual connection, the first extension portion extends downward from one side of the first positioning portion in a direction roughly perpendicular to the first positioning portion; and the negative electrode conductive sheet includes a second positioning portion and a second extension portion, The second positioning portion is combined with the bottom of the second wiring assembly to be electrically connected, and the second extending portion extends downward from one side of the second positioning portion in a direction roughly perpendicular to the second positioning portion. 4 . The lithium battery according to claim 3 , wherein the first positioning portion and the first extension portion are in an inverted L shape, and the second positioning portion and the second extension portion are in an inverted L shape. 5. The lithium battery according to claim 2, 3 or 4, further comprising an insulating rubber sleeve, the insulating rubber sleeve is sleeved on the plurality of positive electrode sheets, the plurality of negative electrode sheets, the plurality of negative electrode sheets, the A plurality of sheet-shaped solid molecular polyelectrolytes, the positive electrode conductive sheet and the outer periphery of the negative electrode conductive sheet.