Patent Description:
The present disclosure relates to a coating die for lithium secondary battery including removable spacer shims.

With the technology development and increased demand for mobile devices, demand for secondary batteries as energy sources has been rapidly increasing. Among such secondary batteries is a lithium secondary battery exhibiting a high energy density and operating voltage, a long cycle lifespan, and a low self-discharge rate, which is now commercialized and widely used.

Also, recently, as interest in environmental issues grows, studies are frequently conducted on an electric vehicle (EV), a hybrid electric vehicle (HEV), etc. which can replace a vehicle using fossil fuels such as a gasoline vehicle and a diesel vehicle, which are one of the main causes of air pollution. A lithium secondary battery having high energy density, discharge voltage and output stability is mainly studied and used as a power source for the electric vehicle (EV), the hybrid electric vehicle (HEV) and the like.

Such a lithium secondary battery is generally manufactured by stacking or winding electrodes of cathode and anode with a separator interposed therebetween, and incorporating them together with an electrolyte solution in a battery case.

Among them, electrodes such as the cathode and the anode are manufactured by applying, drying, and rolling an active material slurry on a current collector, wherein the application of the active material slurry is generally performed by a coating die that discharges the active material slurry.

At this time, a perspective view of the coating die is shown as an example in <FIG> below.

Referring to <FIG> below, such a coating die is composed of an upper coating die <NUM>, a lower coating die <NUM>, and a shim assembly <NUM> interposed therebetween, wherein the shim assembly <NUM> has a structure in which a body shim <NUM> for forming a connection between the upper coating die <NUM> and the lower coating die <NUM>, and spacer shims <NUM>, <NUM>, <NUM> and <NUM> for discharging an insulating liquid are integrated.

However, recently, as the number of lanes for manufacturing electrodes increases and the width of metal foil used as a current collector increases, the integrated shim assembly shows many difficulties in the adjustment of individual slurry width, loading, and mismatch, and has problems with precision design and assembly of the spacer shims in simultaneously forming the insulating liquid and the active material slurry.

Therefore, there is a need to develop a technology that can solve the above problems. <CIT> discloses a die head gasket. <CIT>, <CIT> and <CIT> disclose further die-coaters.

It is an object of the present disclosure to provide a coating die for a lithium secondary battery having a novel structure that allows adjustment of the coating width, loading, and mismatch of an active material slurry or an insulating liquid for each lane as needed.

According to the present invention, there is provided a coating die for a lithium secondary battery,.

In one specific embodiment, the upper die plate may include an insulating liquid injection path into which an insulating liquid is injected.

Wherein, the insulating liquid injection path may be formed from an upper part to a lower part.

In one specific embodiment, the lower die plate is coupled to the upper die plate, and may include a slurry injection path into which the active material slurry is injected, and a manifold that stores the active material slurry, wherein the lower die plate is coupled to the upper die plate by a fixing pin, a fixing bolt, or both.

In one specific embodiment, the body shim is coupled with the upper die plate and the lower die plate, and may have an outlet port that is opened from the manifold toward the outside where the coating is performed and thus discharges the active material slurry stored in the manifold, so as not to cover the manifold formed on the lower die plate and storing the active material slurry.

Wherein, the body shim may be coupled to the upper die plate and the lower die plate by a fixing pin, a fixing bolt, or both.

In the invention, the spacer shims are individually coupled with the upper die plate, the lower die plate, or the upper die plate and the lower die plate, and may include an insulated flow passage that positioned so as to correspond to an insulating liquid injection path of the upper die plate, stores and discharges the insulating liquid injected from the injection path of the upper die plate.

Wherein, the spacer shims may be coupled with the upper die plate, the lower die plate, or the upper and lower die plates by a fixing pin, a fixing bolt, or both.

Further, the fixing pin and the fixing bolt are formed by a structure capable of coupling and removal, and thus, can be formed so that the spacer shims are removable from the coating die.

The spacer shims may consist of one or more numbers or may be included less than or equal to the number of insulating liquid injection paths formed on the upper die plate.

Terms or words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms, and the present disclosure should be construed with meanings and concepts that are consistent with the technical idea of the present disclosure based on the principle that the inventors may appropriately define concepts of the terms to appropriately describe their own disclosure in the best way. Accordingly, the embodiments described herein and the configurations shown in the drawings are only most preferable embodiments of the present invention which is defined by the appended claims. So it should be appreciated that there may be various equivalents and modifications that can replace the embodiments and the configurations at the time at which the present application is filed, and the scope of the present invention is limited by the appended claims and is not limited to the embodiments described below.

Terms or words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms, and the present disclosure should be construed with meanings and concepts that are consistent with the technical idea of the present disclosure based on the principle that the inventors may appropriately define concepts of the terms to appropriately describe their own disclosure in the best way.

Further, the embodiments described herein and the configurations shown in the drawings are only most preferable embodiments of the present invention which is defined by the appended claims. So it should be appreciated that there may be various equivalents and modifications that can replace the embodiments and the configurations at the time at which the present application is filed.

<FIG> is a perspective view of a coating die for a lithium secondary battery according to one embodiment of the present disclosure, <FIG> is a cross-sectional view of the upper die plate <NUM> of the coating die, and <FIG> is a perspective view of one spacer shim <NUM> of the coating die.

In one an example, the present disclosure will be described with reference to <FIG> together.

Referring to <FIG>, the coating die for a lithium secondary battery according to the present disclosure includes an upper die plate <NUM>, a lower die plate <NUM>, and a shim assembly <NUM> interposed between the upper die plate <NUM> and the lower die plate <NUM>, wherein the shim assembly <NUM> includes a body shim <NUM> and one or more spacer shims <NUM>, <NUM>, <NUM> and <NUM>.

More specifically, the upper die plate <NUM> includes coupling holes <NUM> into which fixing pins, fixing bolts, or both for coupling with the lower die plate <NUM> are inserted, and insulating liquid injection paths <NUM> into which an insulating liquid is injected.

Referring to <FIG> together with <FIG>, the insulating liquid injection path <NUM> is formed from the upper part to the lower part and is formed so as to pass through the upper die plate <NUM>, which makes it possible to inject the insulating liquid into the spacer shims <NUM>, <NUM>, <NUM> and <NUM> through the insulating liquid injection paths <NUM>.

The coupling hole <NUM> is formed for coupling between the body shim <NUM> and the lower die plate <NUM>, which will be described later.

Meanwhile, the lower die plate <NUM> includes a slurry injection path into which the active material slurry is injected (not shown in the figure), and a manifold <NUM> that stores the active material slurry.

Here, the slurry injection path has a structure that is connected to the manifold <NUM>. Therefore, the active material slurry injected from the slurry injection path reaches the manifold <NUM> and is stored.

The active material slurry stored in the manifold <NUM> performs electrode coating in the form of being discharged from the outlet port <NUM> of the body shim <NUM> of the shim assembly <NUM> of the coating die in an assembled state , which will be described later.

For this purpose, the lower die plate <NUM> is coupled to the upper die plate <NUM>, wherein since it can be coupled by a fixing pin, a fixing bolt, or both, and the lower die plate <NUM> can also include coupling holes <NUM> and <NUM> that can be coupled with the upper die plate <NUM>.

As a component of the shim assembly <NUM>, the body shim <NUM> has an outlet port <NUM> that is opened from the manifold <NUM> toward the outside where the coating is performed and thus discharges the active material slurry stored in the manifold <NUM>, so as not to cover the manifold <NUM> formed on the lower die plate <NUM> and storing the active material slurry.

As described above, the active material slurry stored in the manifold <NUM> is discharged through the outlet port <NUM>. That is, the body shim <NUM> simply has a '<IMG>' shape.

Further, the body shim <NUM> is coupled with the upper die plate <NUM> and the lower die plate <NUM>. At this time, the coupling of the body shim <NUM> may also be formed by a fixing pin, a fixing bolt, or both, and thus, the body shim <NUM> may include coupling holes <NUM> and <NUM> into which they can be inserted.

Meanwhile, the spacer shims <NUM>, <NUM> , <NUM> and <NUM> included in the coating die <NUM> of the present disclosure are configured to be individually removable.

Specifically, the spacer shims <NUM> , <NUM> , <NUM> and <NUM> are individually coupled with the upper die plate <NUM>, the lower die plate <NUM>, or the upper die plate <NUM> and the lower die plate <NUM>.

In order to be individually removable, the spacer shims <NUM>, <NUM>, <NUM> and <NUM> can be coupled to the upper die plate <NUM>, the lower die plate <NUM>, or the upper die plate <NUM> and the lower plate <NUM> by a fixing pin, a fixing bolt, or both.

Here, the fixing pin and the fixing bolt are formed by a structure capable of coupling and removal, so that the spacer shims <NUM>, <NUM>, <NUM> and <NUM> are formed to be removable from the coating die <NUM>.

At this time, the spacer shims <NUM>, <NUM>, <NUM> and <NUM> may be formed at any position corresponding to the insulating liquid injection path <NUM> of the die upper plate <NUM>, and the width and formation position thereof can be appropriately selected as needed.

Further, since the number of spacer shims <NUM>, <NUM>, <NUM> and <NUM> used can also be selected, the spacer shims may consist of one or more numbers or may be included less than or equal to the number of insulation liquid injection paths formed on the upper plate of the die. Specifically, it is preferable that the number of spacer shims is <NUM> or more, specifically <NUM> or more, and more specifically <NUM> or more.

Therefore, according to the present disclosure, the spacer shims <NUM>, <NUM>, <NUM> and <NUM> is individually removable from the coating die <NUM>, and the number and position of each can be changed, thus enabling adjustment of the coating width, loading, and mismatch between active material slurry and insulating liquid.

In order to show the specific structure of these spacer shims <NUM>, <NUM>, <NUM> and <NUM>, <FIG> schematically shows a perspective view of one of these spacer shims <NUM>.

Referring to <FIG>, the spacer shim <NUM> includes coupling holes 132b and 132c for coupling with the upper die plate <NUM> and/or the lower die plate <NUM>.

Further, the spacer shims <NUM>, <NUM>, <NUM> and <NUM> specifically serve to coat the insulating liquid. Therefore, the spacer shims <NUM>, <NUM>, <NUM> and <NUM> include an insulating flow passage 132a through which the insulating liquid injected from the insulating liquid input path <NUM> of the die upper plate <NUM> is discharged to the outside of the coating die <NUM>.

Therefore, the active material slurry of the manifold <NUM> of the lower die plate <NUM> is discharged and coated by the outlet port <NUM> of the body shim <NUM>, and the insulating liquid is discharged and coated through the insulating flow passages 132a of the spacer shims <NUM>, <NUM>, <NUM> and <NUM>.

Therefore, simultaneous coating of the active material slurry and the insulating liquid is possible.

Any person who has ordinary knowledge in the field to which the present disclosure pertains can make various applications and modifications within the scope of the present invention, which is defined by the appended claims, based on the above contents.

Claim 1:
A coating die for a lithium secondary battery,
the coating die comprising an upper die plate (<NUM>), a lower die plate (<NUM>), and a shim assembly (<NUM>) interposed between the upper die plate (<NUM>) and the lower die plate (<NUM>),
wherein the shim assembly (<NUM>) includes a body shim (<NUM>) and one or more spacer shims (<NUM>, <NUM>, <NUM>, <NUM>), and
wherein the spacer shims (<NUM>, <NUM>, <NUM>, <NUM>) are formed to be individually removable from the coating die,
characterized in that the spacer shims (<NUM>, <NUM>, <NUM>, <NUM>) are individually coupled with the upper die plate (<NUM>), the lower die plate (<NUM>), or the upper die plate (<NUM>) and the lower die plate (<NUM>), and include an insulated flow passage that is positioned so as to correspond to an insulating liquid injection path (<NUM>) of the upper die plate (<NUM>), stores and discharges the insulating liquid injected from the injection path of the upper die plate (<NUM>).