Square lithium battery

Abstract

The utility model discloses a square lithium battery, which relates to the technical field of lithium batteries and comprises a battery stack core, the battery stack core is mounted in an aluminum shell in a matched manner, a tab is mounted at one end of the battery stack core in a matched manner, an opening is formed in one end of the aluminum shell, a battery top cover is mounted at the opening in a matched manner, and the battery top cover is in laser welding with the tab. According to the utility model, the tabs are directly welded on the top cover of the battery, and the welding process of an adapter plate between the top cover of the battery and the tabs is cancelled, so that the assembly process of the battery is simplified, the assembly efficiency is improved, and the cost and the investment of equipment are reduced. According to the utility model, the reinforcing shell is sleeved on the outer side of the square lithium battery, and the plurality of impact force absorbing pieces are mounted on the reinforcing shell in a matched manner, and can absorb impact towards the square lithium battery, so that the safety of the lithium battery is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium batteries, in particular to a square lithium battery. Background Art

[0002] Current lithium batteries generally have two process routes: winding and lamination, depending on the different electrode assembly methods. The lamination process is to cut the positive and negative electrodes into small pieces and stack them with isolation membranes to form small battery cells. The small battery cells are then stacked and connected in parallel to form a large battery cell manufacturing process.

[0003] Chinese patent CN208970674U discloses a square power lithium battery shell structure, which is used to improve the strength of the lithium battery shell and prevent the battery from being damaged by external forces. The structure discloses a shell with multiple grooves, but the structure is relatively simple and is a commonly used reinforcement technology. It cannot well withstand the impact of objects and cannot absorb the impact force. The battery core cannot be better protected by only having a shell with reinforcement grooves.

[0004] However, when assembling square lithium batteries, it is necessary to weld an adapter plate on the battery top cover. The adapter plate is located between the battery top cover and the tabs of the battery stack and is welded, which makes the assembly process more complicated, affects the battery assembly efficiency and increases the investment in battery assembly line equipment. In addition, the adapter plate occupies a certain volume ratio in the battery, affecting the filling amount of active material in the battery. Moreover, when the current square lithium battery is impacted, the battery stack in the lithium battery will bend and break, causing the positive and negative poles in the battery stack to short-circuit and cause fire. Utility Model Content

[0005] The utility model aims to propose a square lithium battery, which eliminates the welding process of the adapter plate between the battery top cover and the pole ear, thereby simplifying the battery assembly process and reducing the equipment investment in the battery assembly line. At the same time, the square lithium battery has better impact resistance and can facilitate the connection of two adjacent square lithium batteries.

[0006] The purpose of the utility model is achieved through the following technical solutions: a square lithium battery, including a battery core, the battery core is installed in an aluminum shell, one end of the battery core is installed with a pole ear, one end of the aluminum shell is provided with an opening and a battery top cover is installed at the opening, the battery top cover and the pole ear are laser welded, the pole ear is directly welded to the battery top cover, the adapter welding process between the battery top cover and the pole ear is eliminated, thereby simplifying the battery assembly process, improving assembly efficiency, reducing costs and equipment investment, and eliminating the adapter brings about an increase in the internal space of the battery, and the height of the battery core in the battery can be appropriately increased to obtain More active material filling can be obtained, thereby improving the volume energy density of the battery. A Mylar film sleeve is provided in the aluminum shell, and the battery core is located inside the Mylar film sleeve. A top patch is also installed on one side of the battery top cover. The Mylar film sleeve has strong insulation, heat resistance and toughness, which can improve the service life of the square lithium battery. A reinforcing shell is sleeved on the aluminum shell. The reinforcing shell can improve the protection effect of the square lithium battery against external impact force, prevent the battery core from being damaged due to impact, short circuit, and fire, thereby increasing the safety of the battery. A number of impact absorbers are installed on the outside of the reinforcing shell.

[0007] An insulating film sleeve is provided in the reinforcing shell, and the aluminum shell is located inside the insulating film sleeve.

[0008] The impact absorbing member comprises an impact absorbing plate, wherein a plurality of impact absorbing grooves are formed on the impact absorbing plate, and the impact absorbing grooves are staggeredly arranged on the impact absorbing plate.

[0009] The impact absorbing plate is equipped with a plurality of clamping plates. The clamping plates are divided into two groups and are symmetrically installed on both sides of the impact absorbing plate. The impact absorbing plate and the clamping plates are connected to form a tree branch shape.

[0010] The clamping plate and the impact force absorbing plate are arranged at an angle of 10-80 degrees, and the clamping plates arranged opposite to each other are clamped and matched with each other.

[0011] The beneficial effects of the utility model are:

[0012] 1. The utility model directly welds the tabs to the battery top cover, eliminating the welding process of the adapter between the battery top cover and the tabs, thereby simplifying the battery assembly process, improving assembly efficiency, reducing costs and equipment investment, and eliminating the adapter increases the internal space of the battery. The height of the battery stack can be appropriately increased to obtain more active material filling, thereby improving the volume energy density of the battery;

[0013] 2. The utility model is provided with a reinforcing shell on the outer side of the square lithium battery, and a plurality of impact absorbers are installed on the reinforcing shell. The impact absorbers include an impact absorbing plate, and a plurality of impact absorbing grooves are provided on the impact absorbing plate, so that the impact absorbing plate is in a bent snake shape. A plurality of clamping plates are installed on the impact absorbing plate, and the clamping plates on the impact absorbing plate are arranged in a tree branch shape. When the square lithium battery encounters an impact, the tree branch-shaped clamping plates can well bear the impacted objects. When the clamping plates transmit the impact to the impact absorbing plates, the impact absorbing plates bend accordingly to prevent the high impact force from impacting the square lithium battery and causing damage to the lithium battery. When the connected square lithium batteries are subjected to impact, the tree branch-shaped clamping plates on the outer sides can also well bear the impacted objects, and the clamping plates will transmit the impact to the impact absorbing plates in the corresponding direction. The impact absorbing plates absorb most of the impact force and then bend accordingly, thereby improving the safety of the square lithium battery.

[0014] The parts not involved in the device are the same as those in the prior art or can be implemented by using the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The figure is a schematic diagram of the basic structure of a square lithium battery of the present invention.

[0016] Figure 2 This is a schematic diagram of the structure of multiple square lithium batteries of the present invention when connected together.

[0017] Figure 3 A square lithium battery of the utility model Figure 2 Top view of .

[0018] Figure 4 This is a schematic diagram of the basic structure of an impact absorber for a prismatic lithium battery according to the present invention.

[0019] Figure 5 A square lithium battery of the utility model Figure 4 Magnified view of part A.

[0020] Figure 6 A square lithium battery of the utility model Figure 3 Enlarged view of part B.

[0021] Figure 7 The figure is a schematic diagram of the location of the impact absorption groove of a prismatic lithium battery according to the present invention.

[0022] Figure 8 This is an exploded diagram of the basic structure of a square lithium battery of the present invention.

[0023] Figure 9A square lithium battery of the utility model Figure 8 Another perspective of the picture. DETAILED DESCRIPTION

[0024] In order to make the technical means, creative features, objectives and effects achieved by the present invention easier to understand, the present invention is further described below in conjunction with specific implementation methods.

[0025] like Figure 8 and Figure 9 As shown, the utility model provides a square lithium battery, including an aluminum shell 102, a battery core 104 is installed in the aluminum shell 102, a pole ear 105 is installed at one end of the battery core 104, an opening is provided at one end of the aluminum shell 102, and a battery top cover 106 is installed at the opening, the battery top cover 106 and the pole ear 105 are laser welded, and the pole ear 105 is directly welded to the battery top cover 106, eliminating the adapter plate welding process between the battery top cover 106 and the pole ear 105, thereby simplifying the battery assembly process, improving assembly efficiency, reducing costs and equipment investment, and eliminating the adapter plate brings about an increase in the internal space of the battery, and the height of the battery core 104 in the battery can be appropriately increased to obtain more active material filling amount, thereby improving the volume energy density of the battery.

[0026] A Mylar film sleeve 103 is provided inside the aluminum shell 102, and the battery core 104 is located inside the Mylar film sleeve 103. A top patch 107 is also installed on one side of the battery top cover 106. The Mylar film sleeve 103 can prevent the core from directly contacting the aluminum shell 102. The Mylar film sleeve 103 has strong insulation, heat resistance and toughness, which can improve the service life of the square lithium battery. A number of reinforcing ribs are opened on the inside of the aluminum shell 102, and the reinforcing ribs are arranged in a mesh pattern, thereby greatly increasing the strength and impact resistance of the aluminum shell 102.

[0027] like Figure 1-7 As shown, a reinforcing shell 201 is sleeved on the aluminum shell 102, an insulating film sleeve 101 is provided inside the reinforcing shell 201, and the aluminum shell 102 is located inside the insulating film sleeve 101. The reinforcing shell 201 can enhance the protection effect of the square lithium battery against external impact, prevent the battery core 104 from being damaged due to impact, short circuit, and fire, thereby increasing the safety of the battery.

[0028] The outer side of the reinforcement shell 201 is equipped with a plurality of impact absorbers 202. The impact absorbers 202 include an impact absorbing plate 2021. The impact absorbing plate 2021 is provided with a plurality of impact absorbing grooves 2022. The impact absorbing grooves 2022 are staggered on the impact absorbing plate 2021, so that the impact absorbing plate 2021 is arranged in a serpentine shape (e.g., Figure 7 shown).

[0029] Several clip-on plates 2023 are installed on the impact absorbing plate 2021. The clip-on plates 2023 are divided into two groups and symmetrically installed on both sides of the impact absorbing plate 2021. In this embodiment, there are four clip-on plates 2023, which are installed in pairs on opposite sides of the impact absorbing plate 2021, so that the impact absorbing plate 2021 and the clip-on plates 2023 are connected to form a tree branch shape.

[0030] The snap-in plate 2023 and the impact absorbing plate 2021 are arranged at an angle of 10-80 degrees, and the snap-in plates 2023 arranged opposite to each other are snap-fitted together. In this embodiment, the snap-in plate 2023 and the impact absorbing plate 2021 are arranged at an angle of 45 degrees, and two adjacent square lithium batteries can be snapped together by the branch-shaped snap-in plate 2023 (such as Figure 6 As shown), after completing the above operations, the two adjacent square lithium batteries are locked in the horizontal direction and can only be removed by plugging and pulling up and down. A plurality of snap-in slots are provided on the reinforcing shell 201, and the impact absorber 202 is snapped into the snap-in slots.

[0031] It should be noted that when the square lithium battery encounters an impact, the tree-branch-shaped clamping plate 2023 can well withstand the impacting object. When the clamping plate 2023 transfers the impact to the impact absorbing plate 2021, the impact absorbing plate 2021 bends accordingly to prevent the high impact force from impacting the square lithium battery and causing damage to the lithium battery. When the connected square lithium batteries are impacted, the outer tree-branch-shaped clamping plate 2023 can also well withstand the impacting object, and the clamping plate 2023 will transfer the impact to the impact absorbing plate 2021 in the corresponding direction. The impact absorbing plate 2021 absorbs most of the impact force and then bends accordingly, thereby improving the safety of the square lithium battery.

[0032] The application principle of the present utility model is as follows: a battery top cover 106 with a large welding platform structure is adopted, the traditional adapter process is cancelled, the height of the battery core 104 is increased, the tab 105 is directly welded to the battery top cover 106, and then the battery top cover 106, top patch 107, Mylar film sleeve 103, insulating film sleeve 101, battery core 104, and aluminum shell 102 are assembled.

Claims

1. A prismatic lithium battery, comprising a battery stack (104), characterized in that: The battery core stack (104) is mounted in an aluminum shell (102); a pole ear (105) is mounted on one end of the battery core stack (104); an opening is provided at one end of the aluminum shell (102); a battery top cover (106) is mounted on the opening; the battery top cover (106) and the pole ear (105) are laser welded; a Mylar film sleeve (103) is provided in the aluminum shell (102); the battery core stack (104) is located on the inner side of the Mylar film sleeve (103); a top patch (107) is mounted on one side of the battery top cover (106); a reinforcing shell (201) is sleeved on the aluminum shell (102); and a plurality of impact absorbers (202) are mounted on the outer side of the reinforcing shell (201).

2. A prismatic lithium battery according to claim 1, characterized in that: An insulating film sleeve (101) is provided inside the reinforcing shell (201), and the aluminum shell (102) is located inside the insulating film sleeve (101).

3. A prismatic lithium battery according to claim 2, characterized in that: The impact force absorbing member (202) comprises an impact force absorbing plate (2021), on which a plurality of impact force absorbing grooves (2022) are provided, and the impact force absorbing grooves (2022) are arranged in a staggered manner on the impact force absorbing plate (2021).

4. A prismatic lithium battery according to claim 3, characterized in that: A plurality of snap-in plates (2023) are mounted on the impact-absorbing plate (2021), and the snap-in plates (2023) are divided into two groups and are symmetrically mounted on both sides of the impact-absorbing plate (2021).

5. A prismatic lithium battery according to claim 4, characterized in that: The snap-in plates (2023) and the impact force absorbing plate (2021) are arranged at an angle of 10-80 degrees, and the snap-in plates (2023) arranged opposite to each other are snap-fitted with each other.

Images