Patent Description:
A tab of a soft-package lithium-ion battery is a single solid metal sheet. The single metal sheet has the advantages of having simple manufacturing process and low cost. However, in high-current batteries, in order to meet the current-carrying requirements of the high-capacity batteries, the thickness of the tabs needs to be increased, and excessively thick tabs increase the difficulty of welding, bending, and other processes in battery manufacturing. A thick and solid tab retains more heat, and failure to dissipate heat in a timely manner affects battery performance and even causes overheating. Documents <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT> represent background art relevant to the present disclosure.

The subject matter of the present invention is defined in the appended claims. A layer-built tab with easy processing and good heat dissipation performance is disclosed, together with an electrode plate, a battery core, and a battery having the layer-built tab.

The layer-built tab includes adhesives and a plurality of metal pieces, the plurality of metal pieces are stacked together, and connected by the adhesives.

The adhesives are arranged between adjacent metal pieces.

A set of the metal pieces from the plurality of metal pieces are provided with through holes, the through holes are filled with the adhesives, the adhesives through and between the metal pieces are connected to form a single body, or a through hole is provided on each alternate metal piece in the plurality of metal pieces; the through holes are filled with the adhesives; the adhesive between and through the alternate metal pieces are connected to form a single body.

Preferably, the plurality of metal pieces have an arc-shaped structure.

Preferably, the plurality of metal pieces includes first metal pieces and second metal pieces, the first metal pieces and the second metal pieces are partially stacked and spaced apart from each other.

Preferably, the plurality of metal pieces includes first metal pieces and second metal pieces, a minimum distance between the first metal pieces and the second metal pieces is different from a minimum distance between adjacent first metal pieces.

An electrode plate, including a current collector, an active material layer, and a layer-built tab as described above, the layer built tab is positioned on the current collector.

Preferably, a plurality of layer-built tabs are positioned on the electrode plate.

A battery core is also disclosed, the battery core includes a first electrode plate, a second electrode plate, and an isolation film; at least one of the first electrode plate or the second electrode plate is the electrode plate described above.

A battery is also disclosed, the battery includes a packaging case and an electrolyte. The battery further includes the above battery core. The electrolyte and the battery core are positioned within the packaging case.

Preferably, a layer-built tab of the battery core is extended out form the packaging case. Adhesives of the battery core are positioned at interfaces between the layer-built tab and the packaging case, and the adhesives are configured for sealing the packaging case.

The plurality of metal pieces in the layer-built tab, the electrode plate, the battery core, and the battery are stacked and spaced apart from each other, which increases the heat dissipation area of the tab while supporting a large current, and effectively improves the heat dissipation capability of the tab.

Implementations of the present disclosure will now be described, by way of embodiments, with reference to the attached figures.

For simplicity and clarity of illustration, where appropriate, same reference numerals have been used among the different figures to indicate corresponding or analogous elements. Additionally, numerous specific details are set forth in order to provide a thorough understanding of the embodiments described herein. However, it will be understood by those of ordinary skill in the art that the embodiments described herein can be practiced without these specific details. In other instances, methods, procedures and components have not been described in detail so as not to obscure the related relevant feature being described. The drawings are not necessarily to scale and the proportions of certain parts may be exaggerated to better illustrate details and features. The description is not to be considered as limiting the scope of the embodiments described herein.

Referring to <FIG>, a layer-built tab <NUM> includes a plurality of metal pieces <NUM> arranged in a stack and adhesives <NUM> for bonding the metal pieces <NUM>. The metal piece <NUM> is, but not limited to, substantially rectangular. In other embodiments, the metal sheet <NUM> may be of other shapes. The adhesive <NUM> is positioned on the side of the metal piece <NUM>. An adhesive <NUM> is provided between adjacent metal pieces <NUM>, and the metal pieces <NUM> are adhered by the adhesive <NUM>, so that the metal pieces <NUM> are kept relatively fixed and spaced apart from each other. Therefore, the heat dissipation area of the layer-built tab <NUM> is increased, and the heat generated by the layer-built <NUM> can be quickly dissipated when there is airflow between the metal pieces <NUM>. Heat dissipation capability of the layer-built tab <NUM> is effectively improved.

The adhesives <NUM> may be hot-melt adhesive sheets, and the adhesives <NUM> are positioned on the sides of adjacent metal pieces <NUM>. The metal pieces <NUM> are adhered by the adhesive <NUM> by means of pressure and heat fusion. The adhesive <NUM> covers substantially a middle region of the metal piece <NUM> and surrounds the middle peripheral side of the metal pieces <NUM>.

In another embodiment, the metal pieces <NUM> may be set in a specific mold, and the adhesive <NUM> is poured on the plurality of the metal pieces <NUM>.

Referring to <FIG>, the layer-built tab <NUM> of the second embodiment is substantially the same as the layer-built tab <NUM> of the first embodiment. The difference is that a plurality of through holes <NUM> are formed on the metal pieces <NUM> of the second embodiment. The through holes <NUM> are substantially located in the middle portion of each metal piece <NUM>. The adhesive <NUM> covers the positions where the through holes <NUM> are located, and the plurality of through holes <NUM> are filled with the adhesive <NUM>, so that the adhesives <NUM> between and through the metal pieces <NUM> are connected to form a single body, providing a strong connection between the metal pieces <NUM>.

In another embodiment, a through hole is provided on each alternate metal piece <NUM> in the plurality of metal pieces, the through holes are filled with the adhesives <NUM>, and the adhesive between and through the alternate metal pieces <NUM> are connected to form a single body. Furthermore, the metal pieces <NUM> provided with through holes and the metal pieces <NUM> without through holes are alternately stacked, or only some of the metal pieces <NUM> are defined with through holes, thereby reducing the strength-reducing effect of the through holes <NUM> and increasing and the conductive performance of the layer-built tab <NUM>.

Referring to <FIG> and <FIG>, the layer-built tab <NUM> of the third embodiment is substantially the same as the layer-built tab <NUM> of the second embodiment. The difference is that the metal pieces <NUM> of the third embodiment have an arc-shaped structure, to fit a battery core <NUM> having a substantially fan-shaped cross section. In other embodiments, there may be multiple shapes and structures of the metal pieces <NUM>, to match with different types of the battery core <NUM>. When stacking the metal pieces <NUM>, through holes <NUM> are defined on each metal piece <NUM>, and then the metal piece <NUM> is placed in a fixture to receive a bending pretreatment according to predetermined requirements, so that the shape and structure of the metal piece <NUM> can be matched with the battery core <NUM>. Curved metal pieces <NUM> are stacked together, and are bonded and fixed by the adhesive <NUM> to form a layer-built tab <NUM>.

In another embodiment, the metal piece <NUM> possesses no through holes <NUM>, and the metal pieces <NUM> may be directly bent and stacked together.

A battery assembly shown in <FIG> includes the battery core <NUM>. The battery core <NUM> has an arc-shaped structure, and its cross section is approximately fan-shaped. The shape and radian of the metal piece <NUM> and the battery core <NUM> are matched. The battery core <NUM> is formed by winding or stacking a first electrode plate and a second electrode plate with opposite polarities. The two layer-built tabs <NUM> arranged in opposite polarities are respectively connected to the first electrode plate and the second electrode plate. The connecting structure of the layer-built tab <NUM> and the electrode plate is shown in <FIG>. The electrode plate includes a current collector <NUM>. The layer-built tab <NUM> is connected to one side of the current collector <NUM>. After the electrode plate is assembled to form the battery core <NUM>, the layer-built tab <NUM> is partially positioned in the battery core <NUM>. Referring to <FIG>, the battery core <NUM> can be packed into a packaging case <NUM> to manufacture a battery <NUM>. The layer-built tab <NUM> extends out of the packaging case <NUM>, and the adhesives <NUM> are positioned at interfaces between the layer-built tab <NUM> and the packaging case <NUM>, to seal the packaging case <NUM>. The packaging case <NUM> is defined with a liquid injection port when the battery core <NUM> is sealed, and the electrolyte flows into the packaging case <NUM> through the liquid injection port. The battery may be, but is not limited to, a lithium ion battery.

Referring to <FIG>, the layer-built tab <NUM> of the fourth embodiment is substantially the same as the layer-built tab <NUM> of the second embodiment, except that the layer-built tab <NUM> includes a plurality of first metal pieces <NUM> and a plurality of second metal pieces <NUM>. The minimum distance between the first metal pieces <NUM> and the second metal pieces <NUM> is different from the minimum distance between two adjacent first metal pieces <NUM>. The adhesive <NUM> positioned on the second metal piece <NUM> extends along the length of the second metal piece <NUM>, so that the adhesive <NUM> on the second metal piece <NUM> extends downward for a distance as shown in <FIG>. Thereby, the second metal piece <NUM> is strengthened, and the mechanical strength of the second metal piece <NUM> is enhanced, avoiding deformation of the second metal piece <NUM>. The extended length of the adhesive <NUM> can be set or calculated according to actual needs. In the fourth embodiment, the shapes of the first metal sheet <NUM> and of the second metal piece <NUM> are the same, the different distances between the first metal pieces <NUM> and the second metal pieces <NUM> are for connecting battery cores with various sizes.

Referring to <FIG> and <FIG>, the layer-built tab <NUM> of the fifth embodiment is substantially the same as the layer-built tab <NUM> of the fourth embodiment, except that the first metal piece <NUM> and the second metal piece <NUM> of the layer-built tab <NUM> have different shapes. The layer-built tab <NUM> is suitable for connecting to a battery core <NUM> having a stepped structure. The first metal piece <NUM> is substantially rectangular, and the second metal piece <NUM> is substantially Z-shaped. The first metal piece <NUM> and the second metal piece <NUM> are partially stacked and are spaced apart from each other. Specifically, one end of the first metal piece <NUM> and one end of the second metal piece <NUM> are stacked, and other end of the first metal piece <NUM> and of the second metal pieces <NUM> are staggered by a middle lateral portion of the "Z" structure.

The battery assembly shown in <FIG> includes the layer-built tabs <NUM> and the battery core <NUM>. The battery core <NUM> includes a first battery core <NUM> and a second battery core <NUM> arranged in a stepped manner. The size of the second battery core <NUM> is smaller than that of the first battery core <NUM>, and the second battery core <NUM> is positioned on a side surface of the first battery core <NUM>. The first metal pieces <NUM> of the layer-built tab <NUM> are connected to the first battery core <NUM>, and the second metal pieces <NUM> of the layer-built tab <NUM> are connected to the second battery core <NUM>. A portion of the second metal piece <NUM> extends out from the second battery core <NUM> and is located under the adhesive <NUM>. Such portion is bent along the shape of the surface of the battery core <NUM> and is adhered to the outer surface of the battery core <NUM>. The battery assembly shown in <FIG> may include two layer-built tabs <NUM>, or may include one layer-built tab <NUM> and one layer-built tab <NUM>. The first metal piece <NUM> and the second metal piece <NUM> of the layer-built tab <NUM> are respectively connected to the first battery core <NUM> and the second battery core <NUM>. Since each metal piece <NUM> is thin and can be easily processed into various shapes, the layer-built tab can be selected or customized according to the actual shape of the battery core <NUM>. The present disclosure does not limit the shape and structure of any metal piece or sheet.

Compared with the conventional single-piece thick tab, the layer-built tab of the present disclosure has the advantages of convenient processing and installation, and can be made to match batteries of different sizes. The metal pieces or sheets are stacked and spaced apart from each other, which increases the heat dissipation area of the tab while supporting large currents, effectively improves the heat dissipation capacity of the tab, and reduces damage caused by high temperatures.

The present disclosure further provides an electrode plate. Referring to <FIG>, the electrode plate includes a current collector <NUM> and an active material layer disposed on the current collector <NUM>. The electrode plate further includes a layer-built tab of any one of the foregoing embodiments or combinations of embodiments. The layer-built tab is arranged in a region where the current collector <NUM> is not provided with the active material layer. A plurality of the layer-built tabs can be positioned on the electrode plate.

The present application further provides an electric core, which includes a first electrode plate, a second electrode plate, and an isolation film. The polarities of the first electrode plate and of the second electrode plate are opposite, and the isolation film is positioned between the first electrode plate and the second electrode plate. At least one of the first electrode plate and the second electrode plate is an electrode plate having a layer-built tab as described above.

The present disclosure further provides a battery, which includes a packaging case, an electrolyte, and the battery core having the layer-built tabs. The electrolyte and the battery core are positioned in the packaging case.

Claim 1:
A layer-built tab (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>), characterized in that, the layer-built tab (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) comprises:
a plurality of metal pieces (<NUM>, <NUM>, <NUM>); and
adhesives (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) arranged between adjacent metal pieces;
the plurality of metal pieces (<NUM>, <NUM>, <NUM>) are stacked, and adhered by the adhesives (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>);
wherein,
- a set of metal pieces (<NUM>, <NUM>), selected from the plurality of metal pieces, are provided with through holes, or
- a through hole (<NUM>) is provided on each alternate metal piece (<NUM>, <NUM>) in the plurality of metal pieces (<NUM>, <NUM>, <NUM>),
wherein the through holes (<NUM>) are filled with the adhesives (<NUM>, <NUM>, <NUM>, <NUM>) and the adhesives (<NUM>, <NUM>, <NUM>, <NUM>) between and through the alternate metal pieces (<NUM>, <NUM>) are connected to form a single body.