CN112582632A

CN112582632A - High-voltage thermal battery

Info

Publication number: CN112582632A
Application number: CN202011423137.XA
Authority: CN
Inventors: 杨波; 范晓华; 吴勇; 陈海峰; 郑毅; 王�华
Original assignee: Beijing Research Institute of Mechanical and Electrical Technology
Current assignee: Beijing Research Institute of Mechanical and Electrical Technology
Priority date: 2020-12-08
Filing date: 2020-12-08
Publication date: 2021-03-30

Abstract

The invention discloses a high-voltage thermal battery, wherein three layers of insulating materials, namely glass fiber cloth (2), natural mica (3) and asbestos paper (4), are arranged between a battery side face battery stack (1) and a shell (5) from inside to outside. Glass fiber cloth (2), natural mica (3), asbestos paper (4), according to 1: 2: 1 layer number ratio assembly. By using various high-performance insulating materials according to a certain proportion and fully utilizing the hybrid protection mechanism among the three materials, the insulating performance in the battery is greatly improved, and fault events such as short circuit burnthrough and the like in the high-voltage battery are prevented.

Description

High-voltage thermal battery

Technical Field

The invention relates to the technical field of thermal battery design, in particular to a high-voltage thermal battery with a safety protection structure design.

Background

The thermal battery is a thermally activated reserve battery, which is a disposable reserve battery activated by using molten salt as electrolyte and melting the molten salt by using a heat source. The unit thermal battery is composed of a battery stack, a battery cover component, a battery shell component and the like, and electric performance output is realized through a battery cover pole. Along with the continuous promotion of the power consumption of current consumer, power is bigger and bigger, and the rated voltage of battery is higher and higher. The increase in the voltage of the thermal battery is achieved by increasing the number of the unit cells connected in series. The high-voltage thermal battery commonly used at present reaches 270V, and the no-load voltage is close to 300V. The voltage of the unit cells is also gradually increased to 75V, even to 150V. The high-voltage thermal battery has high output power and high rated voltage, and brings the design and manufacture problems of high-voltage insulation protection of battery products.

At present, electrical equipment develops towards miniaturization and lightness, and the structural design space of a thermal battery is limited. In a limited structural design space, how to improve the insulativity of the high-voltage unit battery and prevent high-voltage breakdown inside the high-voltage unit battery, the safe insulation design gradually becomes one of the key factors restricting the stable and reliable work of the product. The rated voltage of the traditional thermal battery is 28.5V, and the no-load voltage does not exceed 35V. The insulating property and the safety of a product can be ensured by adopting common heat-insulating materials and structural design, and the battery cell belongs to a mature battery design technology. While the unit cell design of the high voltage battery faces a more severe insulation safety design.

Therefore, in order to further improve the working reliability of the high-voltage thermal battery and solve the problem that the current thermal battery mature process faces high-voltage resistance design, a unit battery process design mode needs to be improved, and the high-voltage thermal battery safety protection design is provided and has very important significance.

Disclosure of Invention

The invention provides a high-voltage thermal battery which is resistant to high voltage and reliable in operation.

The invention relates to a high-voltage thermal battery which comprises a shell 5 and a battery stack 1, wherein three layers of insulating materials, namely glass fiber cloth 2, natural mica 3 and asbestos paper 4, are arranged between the battery stack 1 on the side surface of the battery and the shell from inside to outside.

Further, the glass fiber cloth 2, the natural mica 3 and the asbestos paper 4 are arranged in a mode that 1: 2: 1 layer number ratio assembly.

According to the invention, various high-performance insulating materials are used according to a certain proportion, and the mixed protection mechanism among the three materials is fully utilized, so that the insulating performance in the battery is greatly improved, and fault events such as short circuit burn-through and the like in the high-voltage battery are prevented.

Drawings

FIG. 1 is a schematic diagram of the safety protection structure of the high voltage thermal battery of the present invention.

In the figure, a battery stack-1, glass fiber cloth-2, natural mica-3, asbestos paper-4 and a shell-5

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

The present invention provides a thermal battery having an optimized safety protection structure design. The thermal battery is composed of a shell 5, a battery stack 1, an ignition head and the like. The core chemistry of the cell is in the stack 1. The shell 5 is made of stainless steel, and the heat-insulating layer effectively reduces the heat loss of the cell stack and is isolated from the shell 5. In a limited cell structure space, the electrolyte in the cell stack 1 is in a high-temperature molten state, and a high-voltage use environment requires extremely high insulation performance. The key technical difficulty of high-voltage thermal batteries is to improve the high-voltage insulation performance of the batteries.

On the basis of the structure design technology of a mature battery stack, the invention uses various high-performance insulating materials, including asbestos paper 4, glass fiber cloth 2 and natural mica 3. According to the following steps of 1: 1: 2, the hybrid protection mechanism among the three is fully utilized, the cell stack 1 and the cell shell 5 are separated by a certain safety distance, and the insulating performance is extremely high in a limited space. The principle diagram of the novel protective structure is shown in figure 1. The novel hybrid protection technology effectively enhances the internal insulation performance and the protection performance of the high-voltage thermal battery, and ensures the safe working performance of the high-voltage thermal battery.

A270V high-voltage thermal battery is composed of 4 unit cells, which are cylindrical and have the external size of 40mm x 180 mm. Through design calculation, a single battery with the diameter of 34mm is supposed to be adopted, and the area is 9.07cm 2. The unit cell stack 1 consists of 2 groups of 74 single cells connected in parallel (37 single cells in each group connected in series). 1 layer of

asbestos paper

4, 1 layer of glass fiber cloth 2 and 2 layers of natural mica 3 are adopted as the side insulating material of the cell stack 1, so that the radial insulating distance of the cell stack 1 is increased, and the harm of high-voltage electric arc during the discharge of the cell is prevented. The high-voltage thermal battery with complete structure and excellent performance is formed by adopting an external assembly process.

The "stack assembly" is a key process of the high voltage unit cell. And a key process control card is set according to the assembling and checking points of the battery stack. Key process names and check points are as follows:

1) and checking the edge of the single battery to be neat without edge drop. (100% test)

2) The materials, the quantity and the placement of the components for assembling the cell stack meet the requirements of stacking diagrams and circuit diagrams of the cell stack. (100% test)

3) The diversion strips and the fastening strips are spaced at certain intervals, and the positions of the diversion strips are matched with the positions of the binding posts corresponding to the battery cover and meet the requirements of the placement schematic diagrams of the fastening frame and the current collecting plate assembly. (100% test)

4) The fastening strip should be tightly attached to the cell stack 1, and the upper and lower ends of the ignition strip should be in contact with the upper and lower ignition sheets of the cell stack 1, so as to meet the requirements of the cell stack fastening drawing. (100% test)

5) The height of the cell stack 1 is required. (100% test)

6) The insulating material, the quantity and the type used in the assembly process meet the requirements of design drawings. (100% test)

The above embodiments are only for explaining and explaining the technical solution of the present invention, but should not be construed as limiting the scope of the claims. It should be clear to those skilled in the art that any simple modification or replacement based on the technical solution of the present invention may be adopted to obtain a new technical solution, which falls within the scope of the present invention.

Claims

1. A high-voltage thermal battery comprises a shell (5) and a battery stack (1), and is characterized in that three layers of insulating materials, namely glass fiber cloth (2), natural mica (3) and asbestos paper (4), are arranged between the battery stack (1) on the side face of the battery and the shell from inside to outside.

2. A high voltage thermal battery according to claim 2, characterized in that the glass cloth (2), natural mica (3), asbestos paper (4) are arranged in a ratio of 1: 2: 1 layer number ratio assembly.