Lithium battery with multilayer film heat dissipation structure, and soaking method thereof

A heat dissipation structure, lithium battery technology, applied in the direction of lithium batteries, secondary batteries, non-aqueous electrolyte batteries, etc., can solve the problems of reducing the service life of the battery pack, failing to achieve the expected cooling, and increasing the temperature of the battery core, so as to reduce the overall Effects of temperature rise, waste avoidance, and life extension

Active Publication Date: 2021-11-12
SUZHOU UNIV
View PDF7 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Using the latent heat of PCM in the phase change process to absorb the heat of the battery and prevent the battery temperature from rising too fast has become an important research direction and research hotspot of the battery thermal management system. The temperature during use, because the single layer of phase change material is not in close contact with the battery weakens the heat transfer effect, and the accumulated heat causes the temperature of the battery to increase
[0004]In addition, the temperature rise of the battery in the middle part is faster than the temperature rise of the batteries on both sides of the lithium battery pack assembled by lithium batteries, and the temperature difference varies with the As the charging current increases, the temperature difference can reach more than 10°C in high-current rechargeable batteries. The problem of local overheating will greatly reduce the overall service life of the battery pack. In order to avoid the wooden barrel effect, the soaking treatment of the battery pack is worthy of attention The problem
The current design of the soaking system of the battery pack usually uses a certain distance between the batteries for ventilation or adding a soaking plate. These methods do not design cooling according to the temperature rise characteristics of the batteries in the battery pack, but only for the entire system. A single, same degree of cooling, this type of design will cause waste of resources and increase costs, and the part with a faster temperature rise may not achieve the expected cooling effect

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Lithium battery with multilayer film heat dissipation structure, and soaking method thereof
  • Lithium battery with multilayer film heat dissipation structure, and soaking method thereof
  • Lithium battery with multilayer film heat dissipation structure, and soaking method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0033] Example 1: Performance comparison of a single cell, a single cell wrapped only with phase change material, and a single cell wrapped with phase change material and HDPE

[0034] Sample 1: single cell;

[0035] Sample 2: 6mm expanded graphite wrapped around a single cell;

[0036] Sample 3: A single cell is wrapped with 1.2mm HDPE and 4.8mm expanded graphite;

[0037] The single cells in samples 1 to 3 are the same, the single cell is sample 1, the single cell + graphite is sample 2, the single cell + HDPE / graphite (1:4) is sample 3, the structure of sample 3 is as follows figure 1 As shown: 1 is the battery core, 2 is the HDPE layer, 3 is the graphite layer, and 4 is the shell; research the temperature rise of samples 1 to 3 at a discharge rate of 10C, as shown in figure 2 As shown, the temperature of sample 1 is the fastest in the whole process, and the temperature increase of sample 2 is the smallest before 150s. The temperature of sample 2 and sample 3 is the same...

Embodiment 2

[0038] Example 2: Performance comparison of a single cell, a phase change material wrapped with different thickness ratios, and a single cell of HDPE

[0039] Sample 1: single cell;

[0040] Sample 2: A single cell is wrapped with 1.5mm HDPE and 4.5mm expanded graphite;

[0041] Sample 3: A single cell is wrapped with 1.2mm HDPE and 4.8mm expanded graphite;

[0042] Sample 4: A single cell is wrapped with 1mm HDPE and 5mm expanded graphite;

[0043]The single cells in samples 1 to 4 are the same, and the temperature rise of samples 1 to 4 at a discharge rate of 5C is studied. The temperature changes of each sample are shown in Table 1 below between 710s and 720s. From the results in the table, it can be known that each The temperature of the samples increases with the prolongation of the discharge time. The temperature of sample 1 has reached 38.7°C at 710s, while the temperature of sample 2 wrapped with HDPE and phase change material with a thickness ratio of 1:3 is only 30...

Embodiment 3

[0046] Embodiment 3: a kind of 20V 2Ah battery pack (the HDPE on both sides: graphite is 1:4, the HDPE in the middle: graphite is 1:3)

[0047] Connect five 18650-type lithium batteries in series to form a lithium battery pack in a 20V 2Ah battery pack. The nominal voltage of a single-cell lithium battery is 3.7V, and the actual full-charged single-cell lithium battery can reach 4V. batteries placed side by side, such as image 3 As shown: the batteries at positions 1 and 5 in the figure are batteries on both sides, and the batteries at positions 2-4 in the figure are batteries at the middle position. The preparation of the batteries at both sides and the middle position is as follows:

[0048] Batteries on both sides: Wrap 1.2mm HDPE and 4.8mm expanded graphite on the outside of the single cell, and then wrap it with a heat-conducting shell to obtain batteries placed on both sides.

[0049] The battery in the middle part: wrap 1.5mm HDPE and 4.5mm expanded graphite on the ou...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention relates to a lithium battery with a multilayer film heat dissipation structure, and a soaking method of a battery pack thereof. The lithium battery comprises a battery cell, HDPE, a phase change material and a heating shell from inside to outside, the HDPE is added between the battery cell and the phase change material to form a tightly connected heat conduction layer, the heat resistance is reduced to enhance the heat dissipation of the battery and enhance the safety of the lithium battery, the lithium batteries are connected in series to form a battery pack, and the surface temperature of each single lithium battery in the battery pack is balanced by adjusting the thickness ratio of the combination of the HDPE and the phase change material at different parts in the battery pack, so that the soaking of all lithium battery cells in the battery pack is realized. The soaking method can effectively solve the problems that the service life of the battery pack is shortened and electricity is insufficient due to uneven temperature rise of the battery pack so as to prolong the service life of the battery, in addition, the method is low in implementation cost, the lithium battery with the multilayer film heat dissipation structure can be subjected to mechanical batch production, and industrialization can be achieved.

Description

technical field [0001] The invention relates to the technical field of batteries, in particular to a lithium battery with a multilayer film heat dissipation structure and a heat equalization method for the battery pack thereof. Background technique [0002] In recent years, electric vehicle technology and new energy power station energy storage technology have developed rapidly, and these technologies have higher and higher requirements for the batteries used. Compared with other batteries, lithium batteries have good application prospects due to their high conversion efficiency, high energy density, and environmental friendliness. However, the service life and safety of lithium batteries are greatly affected by temperature. Lithium batteries will generate a lot of heat during use, and the heat will accumulate for a long time, which will cause the internal temperature of the lithium battery to rise, thereby accelerating the decay of battery capacity and reducing the service...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): H01M10/613H01M10/617H01M10/643H01M10/653H01M10/659H01M10/052
CPCH01M10/613H01M10/617H01M10/643H01M10/653H01M10/659H01M10/052Y02E60/10
Inventor 邓业林陈梦婷沙盈盈陈兴际
Owner SUZHOU UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products