Patent Description:
Demand for high-efficiency secondary batteries is rapidly increasing in the fields of mobile devices and electric vehicles. Among such secondary batteries, lithium secondary batteries, which have high energy density, can maintain relatively high voltage, and have a low self-discharge rate, have been commercialized and widely used, and research and development for improving performance are being actively performed.

The lithium secondary batteries can be classified into a lithium ion battery that uses a liquid electrolyte, and a lithium ion polymer battery that uses a polymer solid electrolyte depending on the type of electrolyte.

In the case of the lithium ion battery that uses a liquid electrolyte, it may be usually used in the form in which a cylindrical or rectangular metal can is used as a container and is welded and sealed. Since the can-type secondary battery that uses such a metal can as a container has a fixed shape, it has the drawback of restricting the design of electronic products that uses it as a power source, and it is difficult to reduce the volume. Therefore, a pouch-type secondary battery has been developed and used in which both electrodes, a separation membrane, and an electrolyte are formed into a film, put in a pouch, and sealed.

The pouch-type secondary battery includes, as a basic structure, a battery case and an electrode assembly which are made up of a pouch or the like.

The electrode assembly includes a positive electrode plate, a negative electrode plate, and a separation membrane interposed between the positive electrode plate and the negative electrode plate to electrically insulate the positive electrode plate and the negative electrode plate.

As shown in <FIG>, in an electrode assembly <NUM>, the positive elecrode plate is provided with an anode tab <NUM> provided on one or more regions of the positive electrode plate, and the negative electrode plate is provided with a negative electrode tab <NUM> provided on one or more regions of the negative electrode plate. After the one or more positive electrode tabs <NUM> and negative electrode tabs <NUM> converge in a certain direction, they are joined to the electrode lead <NUM> made of a conductive material by a method such as general resistance welding, ultrasonic welding, laser welding, and riveting. At this time, a sealing film <NUM> may be disposed around the electrode lead <NUM> to ensure an insulated state at a contact portion with the battery case and to increase the degree of sealing.

The electrode lead <NUM> connected and extending in this way performs a function corresponding to a predetermined electrode interface for electrically connecting the secondary battery and an external application device.

In order to bond the electrode lead <NUM> to the electrode tabs <NUM> and <NUM>, the electrode lead <NUM> needs to be transported so as to be located above the electrode tabs <NUM> and <NUM>. The electrode lead <NUM> is transported using a manner of gripping and transporting the electrode lead <NUM> by the gripper <NUM>, and is a manner of applying pressure to the electrode lead <NUM> with the gripper <NUM> to fix the electrode lead <NUM> and transporting it to the electrode tabs <NUM> and <NUM> of the electrode assembly <NUM>.

<FIG> is a side cross-sectional view showing that the gripper <NUM> grips the electrode lead <NUM> in the above-described conventional manner, and in which the electrode lead <NUM> having a flat surface is gripped using the gripper <NUM> having a flat grip surface.

However, if the electrode lead <NUM> and the grip surface are flat as described above, when a change occurs in pressure or surface friction, a phenomenon in which the electrode lead <NUM> is twisted as shown in <FIG> may occur, which may cause dimensional defects in the battery.

Therefore, there is an emerging need for an electrode lead gripper that can solve the above problems.

<CIT> discloses a transport hand suitable for transporting a lead frame.

An object of the present invention is to provide an electrode lead gripper that can transport the electrode lead without twisting the electrode lead, even if pressure or friction changes, by fixing the electrode lead using a gripper.

In order to achieve the above purpose,
the present invention provides a lead gripper that grips and transports an electrode lead as recited in independent claim <NUM>.

In an aspect of the present invention, the lead fixing protrusion may pass through the electrode lead and may be inserted into the groove which accommodates the lead fixing protrusion.

In an aspect of the present invention, the lead fixing protrusion may have a truncated conical shape or a truncated polygonal pyramid shape.

In an aspect of the present invention, the lead fixing protrusion may have the truncated conical shape.

In an aspect of the present invention, the two or more lead fixing protrusions may be included, and the two or more lead fixing protrusions may be located on the grip surface to be spaced apart from each other.

In an aspect of the present invention, the two or more lead fixing protrusions may be located in a horizontal direction or in a vertical direction on the basis of a tip of the arm.

In an aspect of the present invention, the lead gripper may include one to three pairs of arms.

In an aspect of the present invention, the lead fixing hole may have a circular or polygonal shape.

In an aspect of the present invention, the lead fixing hole may have a circular shape.

In an aspect of the present invention, the lead gripper may include a pair of arms,.

In an aspect of the present invention, the lead gripper may include two or more pairs of arms,.

Since the lead gripper of the present invention can fix the electrode lead by the lead fixing protrusion that passes through the electrode lead, it is possible to grip and transport the electrode lead without twisting the electrode lead even when pressure and friction change. This makes it possible to solve problems such as dimensional defects of the battery.

Hereinafter, the present invention will be described in detail based on the accompanying drawings so that a person having ordinary knowledge in the technical field to which the present invention belongs can easily carry it out. This invention may, however, be embodied in many different forms and is not limited to the embodiments set forth herein.

In order to clearly describe the present invention, parts irrelevant to the description have been omitted, and the same or similar components are denoted by the same reference numerals throughout the specification.

Furthermore, terms or words used in the specification and claims should not be construed as being limited to its customary or dictionary meaning, and should be interpreted by the inventors as a meaning and concept consistent with the technical idea of the present invention, based on the principle that the concepts of the terms can be properly defined to describe their invention in the best possible manner.

Embodiments will now be described in detail with reference to the accompanying drawings. This invention may, however, be embodied in many different forms and is not limited to the embodiments set forth herein.

<FIG> and <FIG> are side cross-sectional views that show a lead gripper according to an embodiment of the present invention.

Referring to <FIG> and <FIG>, a lead gripper <NUM> according to one embodiment of the present invention includes an upper arm <NUM> and a lower arm <NUM>, and any one or more grip surfaces of the upper arm <NUM> and the lower arm <NUM> includes one or more lead fixing protrusions <NUM> that pass through the electrode lead to be gripped.

Also, the grip surface of the upper arm <NUM> or the lower arm <NUM> corresponding to the upper arm <NUM> or the lower arm <NUM> including the lead fixing protrusion <NUM> includes grooves <NUM> that accommodate the lead fixing protrusion <NUM>.

In the lead gripper <NUM> of the present invention, other configurations except for the structure of the gripper <NUM> can be configured in the same manner as lead grippers commonly used in this field. That is, as shown in <FIG>, rear end portions of the upper arm <NUM> and the lower arm <NUM> can be coupled to a lead gripper body <NUM>. At this time, the lead gripper body <NUM> may include an arm moving member <NUM> that moves one or more of the upper arm <NUM> and the lower arm <NUM> to enable gripping. The arm moving member <NUM> can be driven by known driving means, for example, hydraulic driving means, mechanical driving means, or the like.

In the lead gripper <NUM> of the present invention, the lead fixing protrusion <NUM> can be inserted through the electrode lead into the groove <NUM> that accommodates the lead fixing protrusion <NUM>. That is, the upper end portion of the lead fixing protrusion <NUM> can be inserted into the groove <NUM> that accommodate the lead fixing protrusion, while penetrating the electrode lead.

For example, when the lower arm <NUM> includes the lead fixing protrusion <NUM>, and the upper arm <NUM> includes the groove <NUM> for accommodating the lead fixing protrusion <NUM>, the electrode lead can be grasped by fitting engagement in which the lower arm <NUM> moves upward so that the lead fixing protrusion <NUM> passes through the electrode lead, and the upper arm <NUM> moves downward to insert the penetrated lead fixing protrusion <NUM> into the groove <NUM>. Also, the electrode lead grip can be released by moving the lower arm <NUM> downward and moving the upper arm <NUM> upward to release the fitting engagement.

Due to the fitting engagement, the electrode lead can be transported to the electrode tab of the electrode assembly without being twisted.

The lead fixing protrusion <NUM> may have a truncated conical shape or a truncated polygonal pyramid shape.

If the lead fixing protrusion <NUM> has a truncated polygonal pyramid shape, since the lead is less likely to be twisted due to the polygonal shape, one or more lead fixing protrusions <NUM> may be included on the grip surface of the upper arm <NUM> or the lower arm <NUM>.

In addition, when the lead fixing protrusion <NUM> has a truncated conical shape, since the penetrated lead fixing protrusion <NUM> is easily twisted, two or more lead fixing protrusions <NUM> may be included on the grip surface of the upper arm <NUM> or the lower arm <NUM>.

Preferably, two or more lead fixing protrusions <NUM> may be included on the grip surface of the upper arm <NUM> or the lower arm <NUM>, and the two or more lead fixing protrusions may be spaced apart from each other on the grip surface.

<FIG> is a diagram showing that the two or more lead fixing protrusions <NUM> are located in a horizontal direction x on the basis of the tip of the arm, and <FIG> shows that the two or more lead fixing protrusions <NUM> are located in a vertical direction y.

The lead gripper <NUM> may include one to three pairs of arms.

<FIG> and <FIG> are plan views showing the electrode lead <NUM> that is gripped by the lead gripper <NUM> according to an embodiment of the present invention.

In order for the lead fixing protrusion <NUM> of the lead gripper <NUM> to pass through the electrode lead <NUM>, the electrode lead <NUM> includes a lead fixing hole <NUM> through which the lead fixing protrusion <NUM> can pass. Specifically, one or more lead fixing holes <NUM> may be included.

Referring to <FIG> and <FIG>, the electrode lead <NUM> includes a joint portion <NUM> joined with the electrode tab, and one or more lead fixing holes <NUM> at one end portion, and a sealing film <NUM> can be placed around the electrode lead <NUM>.

The grip of the electrode lead <NUM> can be performed by making the lead fixing protrusion <NUM> pass through the lead fixing hole <NUM> formed in the electrode lead, and by inserting the lead fixing protrusion <NUM> having passed through the lead fixing hole <NUM> into the groove <NUM> that accommodates the lead fixing protrusion.

For example, when the lower arm <NUM> includes the lead fixing protrusion <NUM> and the upper arm <NUM> includes the groove <NUM> that accommodates the lead fixing protrusion <NUM>, the electrode lead <NUM> can be gripped by the fitting engagement in which the lower arm <NUM> moves upward to allow the lead fixing protrusion <NUM> to pass through the lead fixing hole <NUM> of the electrode lead <NUM>, and the upper arm <NUM> moves downward to insert the lead fixing protrusion <NUM> having passed through the lead fixing hole <NUM> into the groove <NUM>. Further, the grip of the electrode lead <NUM> can be released, by moving the lower arm <NUM> downward and moving the upper arm <NUM> upward to release the fitting engagement.

After the electrode lead <NUM> is gripped, it may be transported such that the joint portion <NUM> of the gripped electrode lead can be located above the electrode tab. After the transportation is completed and the grip of the electrode lead <NUM> is released, since the lead fixing hole <NUM> of the electrode lead <NUM> is no longer needed, it is possible to perform a step of cutting one end portion of the electrode lead <NUM> at which the lead fixing hole <NUM> is located. Cutting can be performed along a cut surface <NUM> of the electrode lead <NUM>.

The lead fixing hole <NUM> may have a circular or polygonal shape, and the shape of the lead fixing hole <NUM> can be determined depending on the shape of the lead fixing protrusion <NUM>. Preferably, lead fixing hole <NUM> may have a circular shape.

Also, the lead fixing holes <NUM> may be included in the same number as the lead fixing protrusions <NUM>, and two or more lead fixing holes <NUM> may be located at one end portion of the electrode lead <NUM> to be separated from each other.

<FIG> is a diagram showing that the two or more lead fixing holes <NUM> are located in the horizontal direction x on the basis of the tip of the electrode lead <NUM>, and <FIG> is a diagram showing that the two or more lead fixing holes <NUM> are located in the vertical direction y.

<FIG> shows that the lead gripper <NUM> according to one embodiment of the present invention grips the electrode lead <NUM>.

Referring to <FIG>, the lead gripper <NUM> according to an embodiment of the present invention can include a pair of arms. Additionally, the grip surface of one of the upper arm <NUM> or the lower arm <NUM> can include two or more lead fixing protrusions <NUM> that pass through the gripped electrode lead <NUM>. The two or more lead fixing protrusions <NUM> may be located in the horizontal direction x or in the vertical direction y on the basis of the tip of the arm. Also, a groove <NUM> that accommodates the lead fixing protrusion <NUM> can be included on the grip surface of the upper arm <NUM> or the lower arm <NUM> corresponding to the upper arm <NUM> or the lower arm <NUM> including the lead fixing protrusion <NUM>.

<FIG> shows a lead gripper <NUM> according to an embodiment of the present invention.

Claim 1:
A lead gripper (<NUM>,<NUM>) that is configured to grip and transport an electrode lead (<NUM>),
wherein the lead gripper (<NUM>,<NUM>) comprises an upper arm (<NUM>) and a lower arm (<NUM>),
wherein one or more grip surfaces of any one of the upper arm (<NUM>) and the lower arm (<NUM>) comprise one or more lead fixing protrusions (<NUM>) that are configured to
pass through one or more lead fixing holes (<NUM>) in the electrode lead to be gripped; and
characterized in that a grip surface of the upper arm (<NUM>) or the lower arm (<NUM>) corresponding to the upper arm (<NUM>) or the lower arm (<NUM>) comprising the lead fixing protrusion (<NUM>) comprises a groove (<NUM>) which is configured to accommodate the lead fixing protrusion (<NUM>).