CN215390536U

CN215390536U - Lithium ion battery pole piece drying device and coating machine

Info

Publication number: CN215390536U
Application number: CN202120833607.3U
Authority: CN
Inventors: 胡同飞; 赵成龙; 程凯
Original assignee: Phylion Battery Co Ltd
Current assignee: Phylion Battery Co Ltd
Priority date: 2021-04-22
Filing date: 2021-04-22
Publication date: 2022-01-04
Anticipated expiration: 2031-04-22

Abstract

The utility model relates to a container comprising a container body; the first feeding hole, the first discharging hole and the second feeding hole are arranged at one end of the box body, and the second discharging hole is arranged at the other end of the box body; a first carrier roller arranged corresponding to the first feed port, a second carrier roller arranged corresponding to the first discharge port, and a third carrier roller arranged corresponding to the second feed port and the second discharge port; the first steering roller is arranged in the middle of the box body and corresponds to the first carrier roller and the second carrier roller; and the heating mechanism and the air outlet are respectively arranged at the lower part and the top of the box body. According to the utility model, the pole piece pre-drying structure is arranged, so that oil stains on the surface of the pole piece can be removed, the pre-drying and the drying after coating can be realized by adopting the same drying device, the equipment cost is reduced, and the structure is simple.

Description

Lithium ion battery pole piece drying device and coating machine

Technical Field

The utility model relates to the technical field of lithium battery production, in particular to a lithium ion battery coating machine.

Background

Lithium ion batteries have been manufactured by coating current collectors for the preparation of pole pieces since the commercialization of sony corporation, a process developed from magnetic tape manufacturing processes. Aluminum foil is generally used for the positive coating, and copper foil is generally used for the negative coating. The preparation of copper foil generally adopts an electrolytic method, the preparation of aluminum foil generally adopts a rolling method, so that oil stain residue is inevitably generated on the surface of the aluminum foil, the slurry can not be completely adhered to a current collector after being dried during coating, and the existence of the oil stain can influence the surface tension of the aluminum foil and the contact angle between the coating slurry and the foil material, so that when intermittent coating is adopted, the slurry can be trailing frequently to generate an undesirable coating shape, as shown in figure 1. The prior art generally ensures the binding effect by increasing the binder, but increasing the proportion of the binder reduces the amount of the positive active material.

Chinese patent CN102327855A discloses a method for improving the adhesion performance of aluminum foil for lithium ion battery positive electrode, which is to perform normal pressure plasma treatment on the surface of the aluminum foil for lithium ion battery before the lithium ion battery positive electrode enters a coater. The adhesive property of the active material of the positive electrode of the lithium ion battery and the substrate can be effectively improved, the capacity of the lithium ion battery is improved, the excellent adhesive property of the positive electrode of the lithium ion battery is ensured on the premise of reducing the using amount of the adhesive, the environment is not polluted, and the adhesive is green and environment-friendly. The defect of the scheme is that after the aluminum foil is subjected to plasma treatment, the aluminum foil needs to be coated within 60 minutes, the requirement on production control is high, and meanwhile, the plasma treatment is complex, the cost is high, and the aluminum foil is difficult to widely apply.

Some coating machines have pre-heat rolls in the coating head, which heat the foil to remove wrinkles or facilitate coating, but this is not very effective. The main reason is that the coating speed is high, the heating time of the aluminum foil passing through the roller is short, and the volatilization temperature of oil is high, so that the temperature of the roller needs to be set to be more than 200 ℃, and oil stains can not be fully volatilized only by passing through the roller for heating.

SUMMERY OF THE UTILITY MODEL

Therefore, the technical problem to be solved by the utility model is to overcome the defects of complex structure, high cost and poor effect in the prior art, and provide a lithium ion battery coating machine which is low in cost and can effectively solve the problem of residual oil stains on the surface of a pole piece.

In order to solve the above technical problem, the present invention provides a drying device for lithium ion battery pole pieces, comprising:

a box body;

the first feeding hole, the first discharging hole and the second feeding hole are arranged at one end of the box body, and the second discharging hole is arranged at the other end of the box body;

a first carrier roller arranged corresponding to the first feed port, a second carrier roller arranged corresponding to the first discharge port, and a third carrier roller arranged corresponding to the second feed port and the second discharge port;

the first steering roller is arranged in the middle of the box body and corresponds to the first carrier roller and the second carrier roller; and the number of the first and second groups,

and the heating mechanism and the air outlet are respectively arranged at the lower part and the top of the box body.

In one embodiment of the utility model, the first turning roll is provided as a first dancer roll.

In one embodiment of the utility model, the box body is divided into a preheating zone, a high-temperature zone and a drying zone, the heating mechanisms are arranged corresponding to the zones and are respectively provided with a first heating mechanism, a second heating mechanism and a third heating mechanism, and the first steering roller is arranged in the high-temperature zone.

In one embodiment of the utility model, the temperature of the high-temperature zone is 150-160 ℃.

In one embodiment of the present invention, the first feed opening and the first discharge opening are located below the second feed opening.

In one embodiment of the utility model, the air outlets are all communicated with an exhaust duct, and the tail end of the exhaust duct is connected with a filter.

In one embodiment of the utility model, a filter plate is arranged above the box body.

The utility model provides a lithium ion battery pole piece coating machine, includes foretell drying device, the drying device front end is provided with unwinding device and scribbles the leftover of bolt of cloth, it is provided with the second steering roll that corresponds first discharge gate and second feed inlet to scribble leftover of bolt of cloth front end, the drying device rear end is provided with the coiling mechanism, be provided with the third steering roll between coiling mechanism and the drying device.

In an embodiment of the utility model, a second floating roller is arranged between the unwinding device and the first feeding hole.

In one embodiment of the utility model, the coating head is a transfer coating mechanism or a slit extrusion coating mechanism.

Compared with the prior art, the technical scheme of the utility model has the following advantages:

according to the drying device, the pole piece pre-drying structure is arranged, so that oil stains on the surface of the pole piece can be removed;

the coating machine provided by the utility model has the advantages that the same drying device is adopted to realize pre-drying and drying after coating, the equipment cost is reduced, the structure is simple, and the problem of residual oil stains on the surface of the pole piece is effectively solved.

Drawings

In order that the present disclosure may be more readily and clearly understood, reference is now made to the following detailed description of the embodiments of the present disclosure taken in conjunction with the accompanying drawings, in which

FIG. 1 is a diagram of intermittent coating effect of a conventional coating machine;

FIG. 2 is a schematic view of a drying apparatus according to the present invention;

FIG. 3 is a schematic view of a coater of the present invention;

FIG. 4 is a diagram showing the effect of gap coating by the coater of the present invention.

The specification reference numbers indicate: 100. a drying device; 110. a box body; 111. a first feed port; 112. a first discharge port; 113. a second feed port; 114. a second discharge port; 115. a preheating zone; 116. a high temperature zone; 117. a drying zone; 121. a first carrier roller; 122. a second carrier roller; 123. a third carrier roller; 130. a first steering roller; 141. a first heating mechanism; 142. a second heating mechanism; 143. a third heating mechanism; 150. an air outlet; 151. an exhaust duct; 152. a filter; 153. a filter plate;

200. an unwinding device; 210. a second dancer roll; 300. coating heads; 310. a second turning roll; 400. a winding device; 410. and a third turning roll.

Detailed Description

The present invention is further described below in conjunction with the following figures and specific examples so that those skilled in the art may better understand the present invention and practice it, but the examples are not intended to limit the present invention.

Referring to fig. 2, a lithium ion battery pole piece drying device 100 of the present invention is shown. The drying apparatus 100 of the present invention includes:

a case 110;

a first feed inlet 111, a first discharge outlet 112 and a second feed inlet 113 which are arranged at one end of the box body 110, and a second discharge outlet 114 which is arranged at the other end of the box body 110;

a first carrier roller 121 arranged corresponding to the first feed port 111, a second carrier roller 122 arranged corresponding to the first discharge port 112, and a third carrier roller 123 arranged corresponding to the second feed port 113 and the second discharge port 114;

a first steering roller 130 disposed in the middle of the box 110 and corresponding to the first idler 121 and the second idler 122; and the number of the first and second groups,

a heating mechanism and an air outlet 150 respectively disposed at the lower portion and the top portion of the case 110.

During operation, the pole piece is unreeled and then enters the drying device 100 from the first feeding hole 111, is supported by the first carrier roller 121 and then bypasses the first steering roller 130, is continuously supported by the second carrier roller 122, is dried by the heating mechanism in the drying device 100 to remove oil stains on the surface of the pole piece, and then leaves the drying device 100. The pole piece is coated outside the drying device 100 and then enters the drying device 100 through the second feeding hole 113 for the second time, the pole piece is supported by the third carrier roller 123, the heating mechanism dries the slurry coating coated on the surface of the pole piece, the dried gas flows out from the air outlet 150, and the dried pole piece leaves the drying device 100 from the second discharging hole 114. In the scheme of this embodiment, need not to add other equipment, let the pole piece dry through drying device 100 earlier on original drying device 100 basis and the coating enters drying device 100 stoving again at last again, simple structure, and the pole piece is long in drying device 100, and drying device 100's temperature is enough, guarantees the volatilizing abundant of pole piece surface greasy dirt. As the pole piece is heated and becomes soft, the tension of the pole piece is changed, and in order to ensure the stability of the tension of the pole piece in the transmission process, the first steering roller 130 is arranged as a first floating roller.

Further, in order to prevent the pole piece from being deformed due to sudden and excessive temperature change, in this embodiment, the inside of the box body 110 is divided into a preheating zone 115, a high temperature zone 116 and a drying zone 117, and the heating mechanisms are arranged as a first heating mechanism 141, a second heating mechanism 142 and a third heating mechanism 143 corresponding to the zones. The first heating mechanism 141 heats the preheating zone 115 to ensure that the temperature of the pole piece rises uniformly and most of the moisture on the coating is evaporated in this zone. The second heating mechanism 142 heats the high temperature zone 116 to further remove moisture from the coating. The third heating mechanism 143 heats the drying zone 117, so that the pole pieces are completely dried. Different heating mechanisms are arranged in each zone, so that the temperature of each zone can be independently adjusted. The heating device in this embodiment is an air blower with a heating wire arranged at the air outlet 150, and the moisture is rapidly evaporated by high temperature and air flow, so as to realize drying. In other embodiments of the present invention, the heating device may have other structures as long as it is sufficient to provide high temperature and air convection. In order to ensure that the oil stains on the surface of the pole piece are dried sufficiently before coating, the first steering roller 130 is arranged in the high-temperature region 116, that is, the pole piece can be in sufficient contact with high temperature, so as to ensure evaporation of the oil stains. The temperature of the high-temperature region 116 is set to be 150-160 ℃. The pole piece can be heated by blast with the highest temperature, and oil stains on the surface of the pole piece can be quickly and fully removed.

Further, most of the pole pieces are located in the preheating zone 115 during degreasing, and in order to ensure that the pole pieces are heated as much as possible in the preheating zone 115, the first feeding hole 111 and the first discharging hole 112 are located below the second feeding hole 113. Therefore, the pole piece is closer to a heat source when oil stain is removed, and the oil stain is easily removed by heating; and the coated pole piece is far away from a heat source, so that uniform temperature rise can be realized, and the uniformity of drying is ensured.

In order to prevent oil stains on the surface of the pole piece and harmful substances in the gas evaporated from the coating, the air outlets 150 are communicated with an exhaust pipe 151, and the tail end of the exhaust pipe 151 is connected with a filter 152. The gas exiting all zones is filtered. The top of box 110 still is provided with filter 153, realizes the secondary filter, further improves the filter effect.

Referring to fig. 3, a lithium ion battery pole piece coater according to the present invention is shown. The coating machine comprises the drying device 100, the unwinding device 200 and the coating head 300 are arranged at the front end of the drying device 100, the second steering roller 310 corresponding to the first discharge hole 112 and the second feed hole 113 is arranged at the front end of the coating head 300, the winding device 400 is arranged at the rear end of the drying device 100, and the third steering roller 410 is arranged between the winding device 400 and the drying device 100. The front end of the utility model refers to the feeding end of the drying device 100 for coating and drying, and the rear end refers to the discharging end of the drying device 100 for coating and drying.

During operation, the pole piece feeding and unwinding device 200 feeds the pole piece into the drying device 100 through the first feeding opening 111, and leaves the drying device 100 through the first steering roller 130. At this time, in order to facilitate coating the surface of the pole piece and ensure that the pole piece enters the drying device 100 again, the pole piece needs to be turned, so a second turning roller 310 is arranged outside the drying device 100. The pole pieces are turned and then coated by the coating head 300, enter the drying device 100 for the second time, and leave the drying device 100 after being dried in the drying device 100. In order to ensure the matching of the pole piece and the winding device 400, the pole piece leaves the drying device 100 and winds up by the winding device 400 by bypassing the third steering roller 410.

After the pole piece enters the drying device 100, the tension changes due to softening by heating, and in order to ensure the tension of the pole piece, a second floating roller 210 is arranged between the unwinding device 200 and the first feed opening 111. The coating head 300 is a transfer type coating mechanism or a slit type extrusion coating mechanism. The coating requirements of continuous coating, gap coating, stripe coating, grid coating and the like can be realized, the coating materials are less, the printing speed is high, the coating precision is high, and the consistency and the stability are good.

In order to verify the effect of the coating machine, the pole piece pre-dried by the coating machine and the pole piece not pre-dried by the traditional coating machine are subjected to peel strength test.

The pole piece is cut into pieces with the same length and width, then the double-sided adhesive tape is pasted on the surface of the pole piece, and the other surface of the double-sided adhesive tape is pasted on the stainless steel plate. The pole piece and the stainless steel plate were fixed to two clamps of a tensile tester, respectively, and then a 180-degree peel test was performed at a speed of 10mm/min, with the test results shown in table 1 below.

TABLE 1

As shown in Table 1, the average value of the peel strength of the non-prebaked electrode sheet of the conventional coater is 315.650N/m, the difference between the maximum value and the minimum value is 206.116N/m, the peel strength is low and the fluctuation is large, and the difference is related to the residual oil stain on the surface of the aluminum foil. The pole piece pre-dried by the coating machine has the advantages that the average value of the peeling strength is 556.868N/m, the difference value between the maximum value and the minimum value is 42.179N/m, the peeling strength is improved, and the consistency is improved. After the peel strength is improved, the bonding effect of the active substances and the current collector is improved, and the content of the bonding agent can be properly reduced, so that the proportion of effective active substances such as ternary or lithium iron phosphate and the like can be properly increased, and the capacity of the battery assembled by the pole piece is improved. Meanwhile, as shown in fig. 4, the pole piece subjected to pre-drying and oil removal has no oil stain, so that the coating tailing phenomenon can be avoided, the lithium precipitation phenomenon that the negative electrode cannot completely cover the positive electrode and the lithium precipitation phenomenon are caused by the fact that the pole lug excess material caused by coating tailing is possibly solved, and the safety performance of the battery is improved.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the utility model.

Claims

1. The utility model provides a lithium ion battery pole piece drying device which characterized in that includes:

a box body;

2. The lithium ion battery pole piece drying device of claim 1, wherein the first turning roll is configured as a first floating roll.

3. The drying device for the lithium ion battery pole piece, according to claim 1, is characterized in that the inside of the box body is divided into a preheating zone, a high temperature zone and a drying zone, the heating mechanism is provided with a first heating mechanism, a second heating mechanism and a third heating mechanism corresponding to each zone, and the first steering roller is provided in the high temperature zone.

4. The drying device for the lithium ion battery pole piece according to claim 3, wherein the temperature of the high temperature region is 150-160 ℃.

5. The drying device for the pole pieces of the lithium ion battery of claim 1, wherein the first feeding hole and the first discharging hole are positioned below the second feeding hole.

6. The drying device for the lithium ion battery pole pieces, according to claim 1, is characterized in that the air outlets are communicated with an exhaust duct, and a filter is connected to the tail end of the exhaust duct.

7. The drying device for the pole pieces of the lithium ion battery as claimed in claim 1, wherein a filter plate is arranged above the box body.

8. A lithium ion battery pole piece coating machine is characterized by comprising the drying device according to any one of claims 1 to 7, wherein an unreeling device and a coating head are arranged at the front end of the drying device, a second steering roller corresponding to a first discharge hole and a second feed hole is arranged at the front end of the coating head, a rolling device is arranged at the rear end of the drying device, and a third steering roller is arranged between the rolling device and the drying device.

9. The lithium ion battery pole piece coating machine of claim 8, wherein a second floating roller is arranged between the unwinding device and the first feeding hole.

10. The lithium ion battery pole piece coating machine of claim 8, wherein the coating head is a transfer coating mechanism or a slit extrusion coating mechanism.