CN108807810A - Solid-state composite lithium battery core pole piece and lithium battery core using same - Google Patents

Abstract

A solid composite lithium battery core plate is formed by sequentially laminating and combining a first anode current collecting part of a first anode current collecting plate, a first anode active substance coating, a first solid electrolyte interlayer, a first cathode active substance coating, a cathode current collecting part of a cathode current collecting plate, a second cathode coating, a second solid electrolyte interlayer, a second anode active substance coating and a second anode current collecting part of a second anode current collecting plate, wherein a lithium battery core is formed by respectively combining insulating glue layers at two ends of a strip-shaped solid composite lithium battery core plate and then winding. Therefore, no matter the battery is used by single piece, stacking or winding, the battery can normally operate in high and low temperature environments through the characteristics of the solid electrolyte coating, and the performance of the battery can be stable, so that the use safety is ensured.

Description

Solid composite lithium battery core pole piece and lithium battery core using the pole piece

technical field

The invention relates to a pole piece of a solid-state composite lithium battery core and a lithium battery core using the pole piece, in particular to a solid-state composite lithium battery core with stable performance at high and low temperatures to ensure safe use.

Background technique

At present, lithium-ion battery cores have developed rapidly in some fields due to their light weight, higher safety factor than steel/aluminum shell batteries, and less explosiveness. However, they are essentially liquid lithium-ion battery cores with replaced packaging. Among them, when the battery core is in the charging and discharging state, short circuit or high temperature environment, so that the temperature of the battery fluid rises to a high temperature above about 75-80 ° C, such as dimethyl carbonate (dimethyl carbonate, DMC) in the electrolyte solution Such organic solvents and some impurities will produce air such as hydrogen, oxygen and carbon dioxide, which will cause inflation and leakage. In this way, not only will the performance of the battery core be reduced, but even an explosion will occur. phenomenon, but there are security concerns.

Furthermore, the manufacturing process of the electrode sheet in the general lithium battery core is roughly divided into two methods: stacking and winding. Both methods are to sandwich the separator paper between the cathode sheet and the anode sheet, and then repeat stacking or winding. After being put into the case, the electrolyte is injected, and finally a steel ball is sealed to form a lithium battery core. However, both the separator paper and the electrolyte are not resistant to high and low temperatures. When the temperature of the battery fluid rises to a high temperature of about 75-80°C, not only will there be a risk of inflation and explosion, but it will also fail to operate at low temperatures. question.

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 solid-state composite lithium battery core pole piece and a lithium battery core using the pole piece, which is to sequentially stack the solid electrolyte interlayer, each coating, and the sheet body, or stack the stacked The structure is wound and formed, so that the conductive performance of the solid electrolyte separator and the characteristics of high and low temperature resistance can prevent the problems of inflation and liquid leakage at high temperatures, so as to ensure safe use, and can be used in low temperature environments work properly.

For reaching above-mentioned purpose, the solid-state composite lithium battery core pole sheet that the present invention establishes comprises a cathode current collector, a first cathode active material coating, a first solid electrolyte interlayer, a first anode active material coating 1. A first anode current collector, a second cathode active material coating, a second solid electrolyte separator, a second anode active material coating and a second anode current collector. Wherein, the cathode collector sheet is composed of a cathode tab and a cathode collector part, the cathode collector part has opposite and corresponding first and second surfaces; one side of the first cathode active material coating is combined with On the first surface of the cathode current collector, the first solid electrolyte separator and the first anode active material coating are sequentially stacked on the other surface of the first cathode active material coating; the first anode current collector is composed of Composed of a first anode tab and a first anode current collecting part, one side of the first anode current collecting part is combined with the other surface of the first anode active material coating. One side of the second cathode active material coating is combined on the second surface of the cathode current collector, and the second solid electrolyte separator and the second anode active material coating are sequentially stacked on the other side of the second cathode active material coating. On one side; the second anode current collection piece is composed of a second anode tab and a second anode current collection part, one side of the second anode current collection part is combined with the other surface of the second anode active material coating.

During implementation, the first surface and the second surface of the cathode collector part are respectively rectangular.

During implementation, the first anode tab and the second anode tab together form an anode tab group, and the anode tab group and the cathode tab are located in opposite positions; the anode tab group and the cathode tab can also be located in the same direction Location.

During implementation, the present invention further includes a first insulating layer and a third insulating layer, the first insulating layer is combined on the first surface of the cathode current collector, and the first insulating layer is adjacent to one side of the first cathode active material coating ; and the third insulating layer is combined on the second surface of the cathode collector part, and the third insulating layer is adjacent to one side of the second cathode coating.

During implementation, the present invention further includes a second insulating layer and a fourth insulating layer, the second insulating layer is combined on the first surface of the cathode current collector, and the second insulating layer is adjacent to the other side of the first cathode active material coating. side; and the fourth insulating layer is combined on the second surface of the cathode collector part, and the fourth insulating layer is adjacent to the other side of the second cathode coating.

The lithium battery core provided in the present invention is formed by winding the strip-shaped solid-state composite lithium battery core pole pieces from the first end toward the second end, wherein the first anode current collecting part of the first end is combined with a A first insulating adhesive layer, a second insulating adhesive layer is combined on the second anode current collecting part at the first end, a third insulating adhesive layer is combined on the first anode current collecting part at the second end, and the second anode current collecting part at the second end is combined with a second insulating adhesive layer. A fourth insulating glue layer is combined on the electrical part.

Description of drawings

FIG. 1 is an exploded view of a preferred embodiment of the core pole piece of a solid-state composite lithium battery according to the present invention.

Fig. 2 is a schematic perspective view of a preferred embodiment of a cathode sheet of a solid composite lithium battery core according to the present invention.

Fig. 3 is a schematic cross-sectional view of A-A' in Fig. 2 .

FIG. 4 is a schematic perspective view of a preferred embodiment of lithium battery cells of the present invention after stacking and forming.

FIG. 5 is a perspective schematic view of a preferred embodiment of the lithium battery core of the present invention when unfolded.

6-8 are three-dimensional appearance schematic diagrams of a preferred embodiment of the lithium battery core of the present invention after winding and molding.

Detailed ways

Please refer to Figs. 1-3, which is a preferred embodiment of the solid-state composite lithium battery core electrode sheet 1 of the present invention, including a cathode current collector sheet 11, a first cathode active material coating, and a strip-shaped sheet respectively. Layer 12, a first insulating layer 13, a second insulating layer 14, a first solid electrolyte interlayer 15, a first anode active material coating 16, a first anode collector sheet 17, a second cathode active Material coating 18 , a third insulating layer 19 , a fourth insulating layer 20 , a second solid electrolyte separator 21 , a second anode active material coating 22 and a second anode collector sheet 23 .

The cathode collector sheet 11 is an aluminum foil, and the cathode collector sheet 11 is composed of a strip-shaped cathode tab 111 and a cathode collector part 112, wherein the cathode collector part 112 has an opposite and corresponding first The surface 113 and the second surface 114 , the first surface 113 and the second surface 114 are respectively rectangular.

The first cathode active material coating 12 and the second cathode coating 18 are respectively lithium sulfur compound coatings, and may also be LiMnO ₂ , LiMn ₂ O ₄ , LiCoO ₂ , Li ₂ Cr ₂ O ₇ , Li ₂ CrO4, LiNiO ₂ , LiFeO ₂ , LiNi _x Co _1-x O ₂ , LiFePO ₄ , LiMn _0.5 Ni _0.5 O ₂ , LiMn _1/3 Co _1/3 Ni _1/3 O ₂ , LiMc _0.5 Mn _1.5 O ₄ , or a combination of the above.

The first insulating layer 13, the second insulating layer 14, the third insulating layer 19 and the fourth insulating layer 20 are respectively insulating glue or insulating varnish, and the first insulating layer 13 and the second insulating layer 14 are respectively combined with the cathode current collecting part 112 on the first surface 113 of the first cathode active material coating layer 12, and are respectively adjacent to both sides of the first cathode active material coating layer 12; the third insulating layer 19 and the fourth insulating layer 20 are respectively combined on the second surface 114 of the cathode current collecting part 112, and respectively Adjacent to both sides of the second cathode coating 18 .

The first solid electrolyte interlayer 15 and the second solid electrolytic interlayer 21 are respectively solid molecular polyelectrolyte coatings, and the solid molecular polyelectrolyte system is ceramic oxide or aluminum oxide, glass ceramics, and can also be high and low temperature resistant. A high molecular polymer, for example: having a repeating unit E ¹ represented by the following general formula I:

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

L ¹ and L ² independently represent the group R ¹ -SO ₃ M;

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 SO ₃ M;

And x represents an integer greater than 10.

The first anode active material coating 16 and the second anode active material coating 22 are lithium mixed metal oxide (lithium mixed metal oxide) coatings, which can also be formed by ball milling commercial silicon powder respectively, and coated on the surface of the silicon material. Carbon coating. The first anode current collector 17 and the second anode current collector 23 are respectively one of aluminum foil or copper foil, and the first anode current collector 17 consists of a strip-shaped first anode tab 171 and a first The anode current collecting part 172 is formed, and the second anode current collecting piece 23 is composed of the elongated second anode tab 231 and the second anode current collecting part 232 .

One side of the above-mentioned first cathode active material coating 12 is combined on the first surface 113 of the cathode current collecting part 112, and the first solid electrolyte separator 15 and the first anode active material coating 16 are sequentially stacked on the first cathode active material coating. The other surface of the material coating 12 , and one side of the first anode current collecting part 172 of the first anode current collecting sheet 17 is bonded to the other surface of the first anode active material coating 16 . In addition, one side of the second cathode coating 18 is combined on the second surface 114 of the cathode current collector 112, and the second solid electrolyte separator 21 and the second anode active material coating 22 are sequentially laminated on the second cathode coating. 18, and one side of the second anode current collecting part 232 of the second anode current collector sheet 23 is bonded to the other surface of the second anode active material coating 22.

Please refer to Fig. 4, after the components of the solid-state composite lithium battery core pole piece 1 of the present invention are stacked and rolled in the above sequence, they can be formed into a sheet, and the first anode tab 171 and the second anode tab The ears 231 together form an anode tab group 24. When the anode tab group 24 and the cathode tab 111 are located in the same direction, and a plurality of solid composite lithium battery core pole pieces 1 are stacked to form a lithium battery core 3, then Provide greater current capacity.

As shown in Figure 5, when the solid composite lithium battery core pole piece 1 of the lithium battery core 3 of the present invention is in the shape of a long strip, the solid composite lithium battery core pole piece 1 has a first end 31 and a second end 32 opposite to each other, Wherein, the first anode collector portion 172 of the first end 31 is bonded with a first insulating adhesive layer 311, the second anode collector portion 232 of the first end 31 is bonded with a second insulating adhesive layer 312, and the second end 32 A third insulating adhesive layer 321 is bonded to the first anode current collecting portion 172 of the second terminal 32 , and a fourth insulating adhesive layer 322 is bonded to the second anode current collecting portion 232 of the second terminal 32 . The first insulating adhesive layer 311 , the second insulating adhesive layer 312 , the third insulating adhesive layer 321 and the fourth insulating adhesive layer 322 are respectively insulating adhesive or insulating varnish. After the strip-shaped solid composite lithium battery core pole piece 1 is wound from the first end 31 to the second end 32, the lithium battery core 3 as shown in FIG. 6 can be formed.

As shown in Figures 7 and 8, when the anode tab group 24 and the cathode tab 111 are in opposite positions, the lithium battery core can also be wound after the strip-shaped solid composite lithium battery core pole piece 1 is wound. 3. It is in the shape of a soft package, a cylinder or a square, and is equipped with various insulating layers to effectively prevent short circuits.

Therefore, the present invention has the following advantages:

1. In the present invention, the solid electrolyte interlayer, each coating layer and the sheet are sequentially laminated to simultaneously replace the existing separator paper and electrolyte. Therefore, not only can the working efficiency be effectively improved to reduce manufacturing and assembly costs, but also in It prevents gas swelling and liquid leakage at high temperature to ensure safe use, and can work normally in low temperature environment to improve performance.

2. The pole piece of the present invention can be used as a single piece or stacked, or after being rolled into a long sheet, it can be wound into lithium battery cores of various shapes such as soft package, cylindrical or square. Therefore, in The processing operation is quite simple, and the use is quite flexible.

The above description is only illustrative, rather than restrictive, to the present invention. Those of ordinary skill in the art understand that many modifications and changes can be made without departing from the spirit and scope defined by the following appended claims. Or equivalent, but all will fall within the protection scope of the present invention.

Claims (9)

1. A solid-state composite lithium battery core pole piece, characterized in that, comprising: A cathode current collector, which is composed of a cathode tab and a cathode current collector, the cathode current collector has opposite and corresponding first and second surfaces; A first cathode active material coating, one side of which is bonded to the first surface of the cathode current collector; A first solid electrolyte separator, one side of which is bonded to the other side of the first cathode active material coating; A first anode active material coating, one side of which is bonded to the other side of the first solid electrolyte separator; A first anode collector piece, consisting of a first anode tab and a first anode collector part, one side of the first anode collector part is bonded to the other side of the first anode active material coating; a second cathode coating, one side of which is bonded to the second side of the cathode current collector; a second solid electrolyte separator, one side of which is bonded to the other side of the second cathode coating; A second anode active material coating, one side of which is bonded to the other side of the second solid electrolyte separator; and A second anode collector sheet is composed of a second anode tab and a second anode collector part, one side of the second anode collector part is bonded to the other side of the second anode active material coating. 2 . The solid-state composite lithium battery core pole piece according to claim 1 , wherein the first surface and the second surface of the cathode current collecting part are respectively rectangular. 3. The solid-state composite lithium battery core pole piece according to claim 1, wherein the first anode tab and the second anode tab jointly form an anode tab group, and the anode tab group and the cathode tab The tabs are in reverse positions. 4. The solid-state composite lithium battery core pole piece according to claim 1, wherein the first anode tab and the second anode tab together form an anode tab group, and the anode tab group and the cathode The tabs are located in the same direction. 5. The solid-state composite lithium battery core pole piece according to any one of claims 1, 2, 3 or 4, further comprising a first insulating layer, which is combined with the cathode current collector The first face of the portion, and the first insulating layer is adjacent to one side of the first cathode active material coating. 6. The solid-state composite lithium battery core pole piece according to claim 5, further comprising a second insulating layer, the second insulating layer is combined on the first surface of the cathode current collecting part, and the first insulating layer is Two insulating layers are adjacent to the other side of the first cathode active material coating. 7. The solid-state composite lithium battery core pole piece according to claim 1, 2, 3 or 4, further comprising a third insulating layer, the third insulating layer is combined with the second part of the cathode collector. and the third insulating layer is adjacent to one side of the second cathode coating. 8. The solid-state composite lithium battery core pole piece according to claim 7, further comprising a fourth insulating layer, the fourth insulating layer is combined on the second surface of the cathode current collecting part, and the first insulating layer is Four insulating layers adjoin the other side of the second cathode coating. 9. A lithium battery core using the solid-state composite lithium battery core pole piece as claimed in claim 1, characterized in that, the solid-state composite lithium battery core pole piece is in the shape of a strip, which has a reverse first end and The second end, the lithium battery core is formed by winding the first end of the pole piece of the solid composite lithium battery core towards the second end, and a first insulating adhesive layer is bonded to the first anode current collecting part of the first end , a second insulating adhesive layer is combined on the second anode current collecting part of the first end, a third insulating adhesive layer is combined on the first anode current collecting part of the second end, and the second anode current collecting part of the second end Combined with a fourth insulating glue layer.