TAB FLATTENING DEVICE

This application relates to a tab flattening device. The tab flattening device includes: a roller configured to convey an electrode plate, a cover, and a flattening portion. The surface of the roller is in contact with the electrode plate in a contact region. The cover surrounds the contact region peripherally and includes a feed-in guide surface oriented toward the contact region. The flattening portion is disposed protrusively on the feed-in guide surface, and located opposite to a tab of the electrode plate. A tab guide surface is formed on the flattening portion. Along a feed-in direction of the electrode plate, the flattening portion is at least partially located upstream of the contact region.

TECHNICAL FIELD

This application relates to the technical field of battery manufacturing, and in particular, to a tab flattening device.

BACKGROUND

Batteries are widely applied to electrical devices such as vehicles, watercraft, or aircraft. To increase the energy density of a battery, a current collector on an electrode plate of the battery shows a tendency to be thinner. However, a thinner current collector makes the tab prone to folding, edge sagging, or bending after the tab is formed.

SUMMARY

In view of this, it is necessary to provide a tab flattening device to solve the problem that a tab is prone to folding, edge sagging, or bending after being formed.

This application provides a tab flattening device, including: a roller configured to convey an electrode plate, a cover, and a flattening portion. The surface of the roller is in contact with the electrode plate in a contact region. The cover surrounds the contact region peripherally and includes a feed-in guide surface oriented toward the contact region. The flattening portion is disposed protrusively on the feed-in guide surface, and located opposite to a tab of the electrode plate. A tab guide surface is formed on the flattening portion. Along a feed-in direction of the electrode plate, the flattening portion is at least partially located upstream of the contact region.

In the technical solution of this application, when the tab flattening device is in use, the electrode plate may be conveyed by the roller, so that the tab of the electrode plate can be passed into the space between the roller and the tab guide surface. In the process of passing the tab of the electrode plate into the space between the roller and the tab guide surface, the flattening portion is at least partially located upstream of the contact region along the feed-in direction of the electrode plate. In addition, the flattening portion is located opposite to the tab of the electrode plate. Therefore, with the electrode plate being passed in progressively, the flattening portion can apply a flattening force to the tab of the electrode plate to unfold the folded part of the tab. In this process, the flattening force is applied by the flattening portion to the tab of the electrode plate before a tab placement part of the electrode plate is passed into the space between the tab guide surface and a position in the contact region on the roller. Understandably, on the one hand, in the process of flattening the tab by the flattening portion, the tab is relatively distant from the contact region of the roller, and the tab is not prone to get jammed between the flattening portion and the roller. In this way, the tab can move smoothly along the feed-in direction as driven by the roller, and can be flattened by the flattening portion. On the other hand, before the tab placement part of the electrode plate contacts the contact region of the roller, the tab has been roughly unfolded. The tab is not prone to get jammed between the flattening portion and the roller in the process of being passed into the space between the tab guide surface and the position in the contact region on the roller. In this way, the folded part of the tab can be flattened to solve the problem of folding, edge sagging or bending of the tab after the tab is formed, and to prevent the folded part of the tab from being jammed.

In an embodiment, the contact region includes a feed-in position from which the electrode plate is rolled in. A distance between a free end of the feed-in guide surface and the electrode plate is greater than a distance between the feed-in guide surface at the feed-in position and the electrode plate. In this way, in the process of passing the electrode plate into the space between the roller and the tab guide surface along the feed-in direction, the distance between the flattening portion disposed protrusively on the feed-in guide surface and the tab of the electrode plate diminishes, thereby unfolding the folded part of the tab more smoothly and playing a role of gradually flattening the tab of the electrode plate.

In an embodiment, the free end points to a part of the feed-in guide surface at the feed-in position along a first direction. The first direction is at an acute angle α1to the feed-in direction of the electrode plate. Understandably, in the process of passing the electrode plate into the space between the roller and the tab guide surface along the feed-in direction, the distance between the flattening portion disposed protrusively on the feed-in guide surface and the tab of the electrode plate diminishes gradually, thereby gradually unfolding the folded part of the tab, gradually flattening the tab of the electrode plate more gently, avoiding damage to the tab during the flattening, and achieving a good effect of flattening the tab.

In an embodiment, the angle α1is 1° to 45°. In this way, the tab can be flattened properly by using the flattening portion.

In an embodiment, the angle α1is 7° to 15°. Such arrangement can not only ensure that the tab can be smoothly passed into the space between the roller and the tab guide surface, but also enable an optimal angle at which the tab is passed into the space between the roller and the tab guide surface, thereby achieving a good flattening effect.

In an embodiment, the tab guide surface is disposed on a side of the flattening portion, the side being away from the feed-in guide surface. An angle between the feed-in guide surface and the tab guide surface is α2, and α1is greater than α2. Understandably, a side of the flattening portion, which is away from the feed-in guide surface, is at a specified distance from the tab between a take-up roller and the tab guide surface. This distance diminishes gradually to ensure that the flattening portion can gradually flatten the tab of the electrode plate more gently.

In an embodiment, a distance between the free end of the feed-in guide surface and the electrode plate is H1, and a width of the tab of the electrode plate is D, satisfying: H1≥1.25×D. Understandably, a turn-up height of an overturned part of the tab is not greater than the width of the tab. The arrangement of H1≥1.25×D can reliably ensure that the flattening portion disposed protrusively on the feed-in guide surface is in contact with the overturned part of the tab so as to apply a flattening force to the folded part of the tab to unfold the folded part, thereby improving the flattening effect.

In an embodiment, a distance between the feed-in guide surface at the feed-in position and the electrode plate is H2, and H2is 0 to 3 mm. Such arrangement not only avoids jamming of the electrode plate caused by a processing error, but also ensures a good flattening effect of the tab.

In an embodiment, the flattening portion includes a plurality of flattening racks arranged at intervals on the feed-in guide surface. Each of the flattening racks extends from the free end of the feed-in guide surface toward a part of the feed-in guide surface at the feed-in position. By using the plurality of flattening racks, the folded part of the tab can be contacted more sufficiently, so as to flatten the folded part of the tab more efficiently.

In an embodiment, each of the flattening racks includes a helical gear section. The helical gear section is disposed obliquely in a width direction of the electrode plate. Such arrangement enables the same helical gear section to contact the folded part of the tab more sufficiently, so as to ensure that a plurality of flattening racks can apply a flattening force to the tab more sufficiently to unfold the folded part of the tab, thereby improving the effect of flattening the tab.

In an embodiment, the free end of the feed-in guide surface points to a part of the feed-in guide surface at the feed-in position along a first direction. An angle between the helical gear section and the first direction is β, and β is 0° to 60°. Such arrangement not only ensures a good effect of flattening the tab, but also avoids an impact caused during the flattening operation.

In an embodiment, at least one of the flattening racks further includes a straight gear section. One end of the straight gear section is connected to the helical gear section in the flattening rack in which the straight gear section is currently located, and another end of the straight gear section extends to the free end of the feed-in guide surface along the first direction. The straight gear section extending along the first direction can contact the turn-up part of the tab. With the tab being passed in, the turn-up part of the tab can be pressed down by using the straight gear section, and the tab is flattened gradually by use of the helical gear section to improve the effect of flattening the tab.

In an embodiment, a width dimension of the plurality of flattening racks arranged on the feed-in guide surface is W1, and W1is greater than a width of the tab. The width of the tab is a dimension of the tab in a direction parallel to a width direction of the electrode plate. The dimension of the folded part of the tab in the direction parallel to the width direction of the electrode plate is not greater than the width of the tab. By setting W1to be greater than the width of the tab, it is ensured that the plurality of flattening racks can contact the folded part of the tab more sufficiently, so as to facilitate the operation of flattening the folded part of the tab and improve the effect of flattening the tab.

In an embodiment, a distance between two adjacent flattening racks is W2, and W2is 3 mm to 5 mm. Such arrangement ensures a good effect of flattening the tab without being prone to jam the tab.

In an embodiment, the cover further includes a curved corner surface connected to the feed-in guide surface. The curved corner surface is in clearance fit with an outer peripheral wall of the roller. After the folded part of the tab is flattened by using the flattening portion disposed protrusively on the feed-in guide surface, the tab of the electrode plate can be passed into the space between the curved corner surface and the outer peripheral wall of the roller. The curved corner surface can guide the tab of the electrode plate, thereby improving the effect of flattening the tab.

In an embodiment, the cover further includes a feed-out guide surface. The feed-out guide surface and the feed-in guide surface are connected to two ends of the curved corner surface respectively in an arc length direction. The disposed feed-out guide surface can guide the electrode plate into the space between the feed-out guide surface and the roller in a case of reverse winding of the electrode plate.

In an embodiment, the free end of the feed-in guide surface includes a first turned-out arc face extending out toward a side away from the electrode plate. The feed-in guide surface is disposed along a tangential direction of the first turned-out arc face. The arc-shaped first turned-out arc face can well protect the electrode plate passed in, and prevent the electrode plate from being damaged by an impact.

DETAILED DESCRIPTION OF EMBODIMENTS

Some embodiments of the technical solutions of this application are described in detail below with reference to the drawings. The following embodiments are merely intended as examples to describe the technical solutions of this application more clearly, but not intended to limit the protection scope of this application.

Unless otherwise defined, all technical and scientific terms used herein bear the same meanings as what is normally understood by a person skilled in the technical field of this application. The terms used herein are merely intended to describe specific embodiments but not to limit this application. The terms “include” and “contain” and any variations thereof used in the specification, claims, and brief description of drawings of this application are intended as non-exclusive inclusion.

In the description of the embodiments of this application, the technical terms “first” and “second” are merely intended to distinguish between different items but not intended to indicate or imply relative importance or implicitly specify the number of the indicated technical features, specific order, or order of precedence. In the description of the embodiments of this application, unless otherwise expressly specified, “a plurality of” means two or more.

Reference to an “embodiment” herein means that a specific feature, structure or characteristic described with reference to this embodiment may be included in at least one embodiment of this application. Reference to this term in different places in the specification does not necessarily represent the same embodiment, nor does it represent an independent or alternative embodiment in a mutually exclusive relationship with other embodiments. A person skilled in the art explicitly and implicitly understands that the embodiments described herein may be combined with other embodiments.

In the description of embodiments of this application, the term “and/or” merely indicates a relationship between related items, and represents three possible relationships. For example, “A and/or B” may represent the following three circumstances: A alone, both A and B, and B alone. In addition, the character “/” herein generally indicates an “or” relationship between the item preceding the character and the item following the character.

In the description of embodiments of this application, the term “a plurality of” means two or more (including two). Similarly, “a plurality of groups” means two or more groups (including two groups), and “a plurality of pieces” means two or more pieces (including two pieces).

In the description of embodiments of this application, a direction or a positional relationship indicated by the terms such as “center”, “longitudinal”, “transverse”, “length”, “width”, “thickness”, “up”, “down”, “before”, “after”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “in”, “out”, “clockwise”, “counterclockwise”, “axial”, “radial”, and “circumferential” is a direction or positional relationship based on the illustration in the drawings, and is merely intended for ease or brevity of description of embodiments of this application, but not intended to indicate or imply that the indicated device or component is necessarily located in the specified direction or constructed or operated in the specified direction. Therefore, such terms are not to be understood as a limitation on embodiments of this application.

In the description of the embodiments of this application, unless otherwise expressly specified and defined, the technical terms such as “mounting”, “concatenation”, “connection”, and “fixing” need to be understood in a broad sense, for example, understood as a fixed connection or a detachable connection or integrally formed; or understood as a mechanical connection or an electrical connection; understood as a direct connection, or an indirect connection implemented through an intermediary; or understood as internal communication between two components or interaction between two components. A person of ordinary skill in the art can understand the specific meanings of the terms in the embodiments of this application according to specific situations.

Batteries are widely applied to electrical devices such as vehicles, watercraft, or aircraft. To increase the energy density of a battery, a current collector on an electrode plate of the battery shows a tendency to be thinner. However, a thinner current collector makes the tab prone to folding, edge sagging, or bending after the tab is formed.

The applicant of this application has found through research that, in the related art, the electrode plate is passed between two limiting components to flatten a tab. However, this manner causes a folded part of the tab to be prone to jam up between the two limiting components, thereby causing damage to the tab.

In view of this, through in-depth research, the applicant of this application has designed a tab flattening device to flatten the folded part of the tab. The tab flattening device can flatten the folded part of the tab without jamming the folded part of the tab, thereby flattening the tab effectively.

The tab flattening device disclosed in an embodiment of this application is applicable to, but not limited to use in, production of batteries. The battery may be a battery cell, a battery module, or a battery pack. The tab flattening device disclosed in this application may be used to flatten a tab, thereby improving the production quality of the battery and safety performance of the battery.

FIG.1is a schematic structural diagram of a tab flattening device10according to an embodiment of this application, andFIG.2is a side view of a tab flattening device10according to an embodiment of this application.

Referring toFIG.1andFIG.2, the tab flattening device10includes a roller100and a tab flattening structure200.

The roller100includes a fixed shaft110and a rotating roller120disposed on the fixed shaft110. The fixed shaft110may be mounted on an appropriate mounting frame. The rotating roller120can rotate relative to the fixed shaft110. The rotating roller120may rotate as driven by a driving mechanism, so as to convey an electrode plate300. In this way, a tab310of the conveyed electrode plate300can be flattened conveniently by using a tab flattening structure200.

FIG.3is a schematic structural diagram of a tab flattening structure200according to an embodiment of this application.

In some embodiments of this application, referring toFIG.1toFIG.3, the tab flattening device10according to an embodiment of this application includes a roller100configured to convey the electrode plate300and a tab flattening structure200. The surface of the roller100is in contact with the electrode plate300in a contact region1001. The tab flattening structure200includes a cover210and a flattening portion220. The cover210surrounds the contact region1001peripherally. The cover210includes a feed-in guide surface211oriented toward the contact region1001. The flattening portion220is disposed protrusively on the feed-in guide surface211, and located opposite to a tab310of the electrode plate300. A tab guide surface2201is formed on the flattening portion220. Along a feed-in direction of the electrode plate300, the flattening portion220is at least partially located upstream of the contact region1001.

The “cover210” means a component that can surround the roller100peripherally and can be mounted to the roller100. The cover210is roughly plate-shaped. The cover210may include a curved plate portion, and may include a straight plate portion, and may include both a curved plate portion and a straight plate portion, without being particularly limited herein.

The “flattening portion220” means a component disposed protrusively on the feed-in guide surface211and capable of forming a tab guide surface2201, so that a flattening force can be applied to the tab310of the conveyed electrode plate300to unfold a folded part of the tab310. As an example, the flattening portion220roughly assumes a comb teeth shape, and can apply a flattening force to the tab310of the conveyed electrode plate300to unfold the folded part of the tab310.

The “feed-in guide surface211” means a surface capable of guiding the tab310passed into the space between the roller100and the feed-in guide surface211.

The “free end2111” means a side away from the contact region1001on the feed-in guide surface211. The tab310can pass through the free end2111of the feed-in guide surface211, and be passed into the space between the contact region1001and the flattening portion220.

The “contact region1001” means a region in rough contact with the electrode plate300in a surface of the roller100. The flattening portion220can be at least partially located upstream of the contact region1001, so as to flatten the tab310of the electrode plate300by making better use of the flattening portion220. As an example, the electrode plate300can be disposed around the surface of the roller100as conveyed by the roller100, so as to contact the contact region1001. The contact region1001includes a part around which the electrode plate300is disposed on the surface of the roller100. Alternatively, the electrode plate300may contact the contact region1001in other ways, without being particularly limited herein.

The “tab guide surface2201” means a surface capable of applying a flattening force to the tab310of the electrode plate300to unfold a folded part of the tab310. The tab guide surface2201may be a whole surface, or may be formed of a plurality of independent surfaces, or may be a discontinuous surface formed of a plurality of linear parts, without being particularly limited herein.

When the tab flattening device10is in use, the electrode plate300may be conveyed by the roller100, so that the tab310of the electrode plate300can be passed into the space between the roller100and the tab guide surface2201. In the process of passing the tab310of the electrode plate300into the space between the roller100and the tab guide surface2201, the flattening portion220is at least partially located upstream of the contact region1001along the feed-in direction of the electrode plate300. In addition, the flattening portion220is located opposite to the tab310of the electrode plate300. Therefore, with the electrode plate300being passed in progressively, the flattening portion220can apply a flattening force to the tab310of the electrode plate300to unfold the folded part of the tab310. In this process, the flattening force is applied by the flattening portion220to the tab310of the electrode plate300before a tab310placement part of the electrode plate300is passed into the space between the tab guide surface2201and a position in the contact region1001on the roller100. Understandably, on the one hand, in the process of flattening the tab310by the flattening portion220, the tab310is relatively distant from the contact region1001of the roller100, and the tab310is not prone to get jammed between the flattening portion220and the roller100. In this way, the tab310can move smoothly along the feed-in direction F as driven by the roller100, and can be flattened by the flattening portion220. On the other hand, before the tab310placement part of the electrode plate300contacts the contact region1001of the roller100, the tab310has been roughly unfolded. The tab310is not prone to get jammed between the flattening portion220and the roller100in the process of being passed into the space between the tab guide surface2201and the position in the contact region1001on the roller100. In this way, the folded part of the tab310can be flattened to solve the problem of folding, edge sagging or bending of the tab after the tab310is formed, and to prevent the folded part of the tab310from being jammed.

It is hereby noted that, before the electrode plate300is passed in, the folded part of the tab310of the electrode plate300is turned upward, so that it is convenient to flatten the tab310of the electrode plate300by using the tab flattening structure200disposed around the roller100.

In some embodiments of this application, referring toFIG.2andFIG.3, the contact region1001includes a feed-in position from which the electrode plate300is rolled in. A distance between a free end2111of the feed-in guide surface211and the electrode plate300is greater than a distance between the feed-in guide surface211at the feed-in position and the electrode plate300.

With reference toFIG.2, the distance between the free end2111of the feed-in guide surface211and the electrode plate300is H1, and the distance between the feed-in guide surface211at the feed-in position and the electrode plate300is H2, satisfying: H1>H2.

In this way, in the process of passing the electrode plate300into the space between the roller100and the tab guide surface2201along the feed-in direction F, the distance between the flattening portion220disposed protrusively on the feed-in guide surface211and the tab310of the electrode plate300diminishes, thereby unfolding the folded part of the tab310more smoothly and playing a role of gradually flattening the tab310of the electrode plate300.

In some embodiments of this application, referring toFIG.2andFIG.3, the free end2111points to a part of the feed-in guide surface211at the feed-in position along a first direction F1. The first direction F1is at an acute angle α1to the feed-in direction F of the electrode plate300.

Referring toFIG.3, the feed-in guide surface211at the feed-in position roughly corresponds to the position a inFIG.3.

Understandably, in the process of passing the electrode plate300into the space between the roller100and the tab guide surface2201along the feed-in direction F, the distance between the flattening portion220disposed protrusively on the feed-in guide surface211and the tab310of the electrode plate300diminishes gradually, thereby gradually unfolding the folded part of the tab310, gradually flattening the tab310of the electrode plate300more gently, avoiding damage to the tab310during the flattening, and achieving a good effect of flattening the tab310.

In some embodiments of this application, the angle α1is 1° to 45°, so that the tab310can be flattened properly by using the flattening portion220.

In some embodiments, α1is 1° to 30°. If the angle α1is overly large, the tab310may fail to be passed into the space between the roller100and the tab guide surface2201at an optimum angle, and the flattening effect is inferior. If the angle α1is overly small, the angle adversely affects the passing of the tab310into the space between the roller100and the tab guide surface2201. In view of this, α1needs to fall within an appropriate range. For example, α1is set to 1° to 30°, thereby ensuring smooth passing of the tab310into the space between the roller100and the tab guide surface2201, ensuring an optimum angle at which the tab310is passed into the space between the roller100and the tab guide surface2201, and achieving a good flattening effect.

The “angle” at which the tab is passed in is α1.

In some embodiments of this application, the angle α1is 7° to 15°. By using the flattening portion220, the folded part of the tab310can be flattened gradually, and the flattening effect is relatively good.

In some embodiments of this application, referring toFIG.2andFIG.4, the tab guide surface2201is disposed on a side of the flattening portion220, the side being away from the feed-in guide surface211. An angle between the feed-in guide surface211and the tab guide surface2201is α2, and α1is greater than α2.

Understandably, the tab guide surface2201is at an acute angle α0to the feed-in direction F of the electrode plate300, and α0=α1−α2. This enables the tab guide surface2201to be at a specified distance from the tab310passed into the space between the roller100and tab guide surface2201. This distance diminishes gradually to ensure that the flattening portion220can gradually flatten the tab310of the electrode plate300more gently.

α2is 1° to 10°. If α2is overly large, α0will be overly small and adversely affect the tab310being passed in. If α2is overly small, α0will be overly large and lead to an overly distance between the tab guide surface2201and the tab310passed in, thereby impairing the flattening effect. In view of this, α2needs to be controlled to fall within an appropriate range. For example, α2is set to 1° to 10°, and α2is set to be smaller than α1. In this way, it is ensured that the tab310can be smoothly passed into the space between the roller100and the tab guide surface2201, and the tab310of the electrode plate300can be gradually flattened gently by using the flattening portion220.

In some embodiments of this application, referring toFIG.1toFIG.3, a distance between the free end2111of the feed-in guide surface211and the electrode plate300is H1, and a width of the tab310of the electrode plate300is D, satisfying: H1≥1.25×D. The width of the tab310is a dimension of the tab310in a direction parallel to a width direction of the electrode plate300.

The width direction of the electrode plate300is perpendicular to a length direction of the electrode plate300. By satisfying H1≥1.25×D, the distance between the free end2111of the feed-in guide surface211and the electrode plate300is caused to be greater than 1.25 times the width of the tab310.

Understandably, a turn-up height of an overturned part of the tab310is not greater than the width of the tab310. The arrangement of H1≥1.25×D can reliably ensure that the flattening portion220disposed protrusively on the feed-in guide surface211is in contact with the overturned part of the tab310so as to apply a flattening force to the folded part of the tab310to unfold the folded part, thereby improving the flattening effect.

In some embodiments, referring toFIG.2andFIG.4, the dimension of the feed-in guide surface211along the first direction F1is L1. L1is roughly inversely proportional to α1. In this way, it is ensured that the tab310can be passed into the space between the roller100and the tab guide surface2201at an optimum angle and can be flattened by the flattening portion220with an appropriate length, thereby achieving a good effect of flattening the tab310.

In some embodiments of this application, a distance between the feed-in guide surface211at the feed-in position and the electrode plate300is H2, and H2is 0 to 3 mm.

If H2is overly small, the electrode plate300may be jammed due to a processing error. If H2is overly large, the effect of flattening the tab310may be impaired.

Therefore, H2needs to be controlled to fall within an appropriate range. For example, H2is set to 0 to 3 mm. Specifically, H2is appropriately 1 mm.

In some embodiments of this application, referring toFIG.3, the flattening portion220includes a plurality of flattening racks221arranged at intervals on the feed-in guide surface211. Each of the flattening racks221extends from the free end2111of the feed-in guide surface211toward a part of the feed-in guide surface211at the feed-in position.

The “flattening rack221” is a bar-shaped component disposed protrusively on the feed-in guide surface211and extending from the free end2111toward a part of the feed-in guide surface211at the feed-in position. The flattening rack221is roughly comb-shaped, and can apply a flattening force to the tab310to unfold the folded part of the tab310.

By using the plurality of flattening racks221, the folded part of the tab310can be contacted more sufficiently, so as to flatten the folded part of the tab310more efficiently.

In some embodiments of this application, referring toFIG.3andFIG.5, each of the flattening racks221includes a helical gear section2211. The helical gear section2211is disposed obliquely in a width direction of the electrode plate300.

The helical gear section2211of the flattening rack221is a part disposed at an angle to the first direction F1on the flattening rack221. The helical gear section2211of the flattening rack221extends along a second direction F2. The second direction F2is at an angle to the first direction F1. The second direction F2is parallel to the feed-in guide surface211. Specifically, in the embodiments shown inFIG.3andFIG.5, the first direction F1is the length direction of the feed-in guide surface211. The width direction of the feed-in guide surface211is parallel to the width direction of the electrode plate300. The second direction F2tilts relative to the length direction of the feed-in guide surface211, and also tilts relative to the width direction of the feed-in guide surface211.

By tilting the helical gear section2211in the width direction of the electrode plate300, the same helical gear section2211is enabled to contact the folded part of the tab310more sufficiently, so as to ensure that a plurality of flattening racks221can apply a flattening force to the tab310more sufficiently to unfold the folded part of the tab310, thereby improving the effect of flattening the tab310.

In some embodiments of this application, referring toFIG.3andFIG.5, the free end2111of the feed-in guide surface211points to a part of the feed-in guide surface211at the feed-in position along a first direction F1. An angle between the helical gear section2211and the first direction F1is β, and β is 0° to 60°.

As mentioned above, the feed-in guide surface211at the feed-in position roughly corresponds to the position a inFIG.3. In addition, β is set to a value in an appropriate range (0° to 60°). Such arrangement not only ensures a good effect of flattening the tab310, but also avoids an impact caused during a flattening operation.

In some embodiments, β is 5° to 60°. If β is overly small, in a process of being passed in, the tab needs to travel a long distance before the helical gear section2211can sufficiently contact the folded part of the tab310. Consequently, the effect of flattening the tab310is inferior, the flattening efficiency is low, and the debugging efficiency is also impaired. If β is overly large, the helical gear section2211contacts the folded part of the tab310quickly, and an impact is prone to occur. In view of this, β needs to be set to a value in an appropriate range. For example, β is set to 5° to 60°, thereby not only ensuring a good effect of flattening the tab310, but also avoiding an impact caused during the flattening operation.

In some embodiments of this application, referring toFIG.5, at least one of the flattening racks221further includes a straight gear section2212. One end of the straight gear section2212is connected to the helical gear section2211in the flattening rack221in which the straight gear section is currently located, and another end of the straight gear section extends to the free end2111of the feed-in guide surface211along the first direction F1.

The straight gear section2212is roughly parallel to the first direction F1. The first direction F1is a length direction of the feed-in guide surface211.

“At least one of the flattening racks221further includes a straight gear section2212” means: one of the flattening racks221further includes a straight gear section2212; or, a plurality of the flattening racks221each include a straight gear section2212; or, all the flattening racks221each include a straight gear section2212, without being particularly limited herein.

In this way, the straight gear section2212extending along the first direction F1can contact the turn-up part of the tab310. With the tab310being passed in, the turn-up part of the tab310can be pressed down by using the straight gear section2212, and the tab310is flattened gradually by use of the helical gear section2211to improve the effect of flattening the tab310.

In some embodiments of this application, referring toFIG.5, a width dimension of the plurality of flattening racks221arranged on the feed-in guide surface211is W1, and W1is greater than a width of the tab310. The width of the tab310is a dimension of the tab310in a direction parallel to a width direction of the electrode plate300.

The width dimension of the plurality of flattening racks221arranged on the feed-in guide surface211means a dimension occupied by the plurality of flattening racks221on the feed-in guide surface211along a third direction F3. The third direction F3is perpendicular to the first direction F1, and is parallel to the feed-in guide surface211. Specifically, in the embodiment shown inFIG.5, the first direction F1is the length direction of the feed-in guide surface211, and the third direction F3is the width direction of the feed-in guide surface211.

Understandably, the dimension of the folded part of the tab310in the direction parallel to the width direction of the electrode plate300is not greater than the width of the tab310. In this way, by setting Wi to be greater than the width of the tab310, it is ensured that the plurality of flattening racks221can contact the folded part of the tab310more sufficiently, so as to facilitate the operation of flattening the folded part of the tab310and improve the effect of flattening the tab310.

In some embodiments of this application, referring toFIG.5, a distance between two adjacent flattening racks221is W2, and W2is 3 mm to 5 mm.

If W2is overly small, the processing will be adversely affected, and the two adjacent flattening racks221are prone to clamp the tab310to give rise to tearing. If W2is overly large, the flattening effect will be impaired. Therefore, W2needs to fall within an appropriate range. For example, W2is set to 3 mm to 5 mm, so as to not only ensure a good effect of flattening the tab310, but also make the tab310not prone to be clamped.

In some embodiments of this application, referring toFIG.4in conjunction withFIG.6toFIG.8, the cover210further includes a curved corner surface212connected to the feed-in guide surface211. The curved corner surface212is in clearance fit with an outer peripheral wall of the roller100.

The “curved corner surface212” is an arc-shaped surface connected to the feed-in guide surface211and capable of being in clearance fit with the outer peripheral wall of the roller100.

After the folded part of the tab310is flattened by using the flattening portion220disposed protrusively on the feed-in guide surface211, the tab310of the electrode plate300can be passed into the space between the curved corner surface212and the outer peripheral wall of the roller100. The curved corner surface212can guide the tab310of the electrode plate300, thereby improving the effect of flattening the tab310.

In some embodiments of this application, referring toFIG.4andFIG.8, the cover210further includes a feed-out guide surface213. The feed-out guide surface213and the feed-in guide surface211are connected to two ends of the curved corner surface212respectively in an arc length direction.

The “feed-out guide surface213” is a surface that guides the tab310to pass through and move out of the region between the feed-out guide surface213and the roller100.

On the one hand, after the flattening portion220flattens the folded part of the tab310and after the curved corner surface212guides the tab310of the electrode plate300, the electrode plate300passes through and moves out of the region between the feed-out guide surface213and the roller100as guided by the feed-out guide surface213. On the other hand, the electrode plate300is usually wound on a reel of the electrode plate. One end of the electrode plate300is conveyed by the roller100. In this process, the tension of the electrode plate300is inevitably adjusted, thereby resulting in reverse winding of the electrode plate300. In this case, the disposed feed-out guide surface213can guide the electrode plate300to get passed into the space between the feed-out guide surface213and the roller100during the reverse winding of the electrode plate300.

In some embodiments of this application, referring toFIG.2andFIG.7, the feed-out guide surface213is at an acute angle α3to a feed-out direction of the electrode plate300, and α3is 1° to 45°. Understandably, the feed-out direction of the electrode plate300is parallel to the feed-in direction F of the electrode plate300. Therefore, the feed-out guide surface213is also at an acute angle α3to the feed-in direction F of the electrode plate300, and α3is 1° to 45°. This not only ensures that the electrode plate300is passed out smoothly, but also prevents the feed-out guide surface213from impacting and breaking the electrode plate300during the reverse winding of the electrode plate300.

In some embodiments, referring toFIG.4andFIG.8, the dimension of the feed-out guide surface213along the length direction of the feed-out guide surface213is L2, and L2is roughly inversely proportional to α3.

In some embodiments, referring toFIG.2andFIG.7, the distance between a feed-out side of the feed-out guide surface213and the electrode plate300is H3. Similarly, H3≥1.25×D, thereby more reliably preventing the feed-out guide surface213from impacting and breaking the electrode plate300during the reverse winding of the electrode plate300.

In some embodiments of this application, referring toFIG.4andFIG.8, the feed-out guide surface213is at an angle γ to the feed-in guide surface211, and γ is 20° to 110°.

If γ is overly small, the tab310is prone to be jammed. If γ is overly large, the flattening effect of the tab flattening structure200is inferior. Therefore, γ needs to fall within an appropriate range to ensure a good flattening effect and avoid jamming of the tab310.

In some embodiments of this application, referring toFIG.4andFIG.8, the free end2111of the feed-in guide surface211includes a first turned-out arc face214extending out toward a side away from the electrode plate300. The feed-in guide surface211is disposed along a tangential direction of the first turned-out arc face214.

Understandably, the arc-shaped first turned-out arc face214can well protect the electrode plate300passed in, and prevent the electrode plate300from being damaged by an impact.

In some embodiments of this application, referring toFIG.4andFIG.8, a second turned-out arc face215is disposed on a side of the feed-out guide surface213, the side being away from the curved corner surface212. The second turned-out arc face extends out toward the side away from the electrode plate300. The feed-out guide surface213is disposed along a tangential direction of the second turned-out arc face215.

Understandably, the arc-shaped second turned-out arc face215can well protect the electrode plate300that is reversely passed in during the reverse winding, and prevent the electrode plate300from being damaged by an impact.

In some embodiments of this application, referring toFIG.1andFIG.3, the tab flattening device10further includes a mounting base230. The mounting base230is a component capable of putting the cover210on the roller100and making the cover210surround the roller100peripherally. As an example, the mounting base230is sleeved on the fixed shaft110of the roller100. A first mounting hole216is created on the cover210, and a second mounting hole is created on the mounting base230. The cover210is connected to the mounting base230by means of the first mounting hole216and the second mounting hole, so that the cover210is disposed on the roller100and the cover210is caused to surround the roller100peripherally. The first mounting hole216and the second mounting hole may be threaded holes. The cover210may be disposed on the roller100through bolts217that fit the threaded holes.

In some embodiments of this application, referring toFIG.1toFIG.5, the tab flattening device10includes a roller100and a tab flattening structure200. The tab flattening structure200includes a cover210and a flattening portion220. The surface of the roller100is in contact with the electrode plate300in the contact region1001. The cover210surrounds the contact region1001peripherally. The cover210includes a feed-in guide surface211oriented toward the contact region1001. The flattening portion220is disposed protrusively on the feed-in guide surface211, and located opposite to the tab310of the electrode plate300. A tab guide surface2201is formed on the flattening portion220. Along a feed-in direction of the electrode plate300, the flattening portion220is at least partially located upstream of the contact region1001. The distance (H1) between the free end2111of the feed-in guide surface211and the electrode plate300is greater than the distance (H2) between the feed-in guide surface211at the feed-in position and the electrode plate300.

In this way, in the process of passing the electrode plate300into the space between the roller100and the tab guide surface2201along the feed-in direction F, the distance between the flattening portion220disposed protrusively on the feed-in guide surface211and the tab310of the electrode plate300also diminishes, thereby unfolding the folded part of the tab310more smoothly and playing a role of gradually flattening the tab310of the electrode plate300.

The technical features in the foregoing embodiments may be combined arbitrarily. For brevity, not all possible combinations of the technical features in the embodiments are described. However, to the extent that no conflict exists, all such combinations of the technical features are considered falling within the scope hereof.

The foregoing embodiments merely describe several implementations of this application. The description is relatively detailed, but constitutes no limitation on the patent scope hereof. It is hereby noted that several variations and improvements, which may be made to the embodiments by a person of ordinary skill in the art without departing from the concept of this application, fall within the protection scope of this application. Therefore, the protection scope of this application is subject to the claims appended hereto.