Application of insulating thin-coated powder coatings on batteries of new energy vehicles

From the performance requirements of thin-coated powder coatings with excellent insulation properties, select appropriate materials under the condition of a certain spray thickness;

The influence of different types of resins, assimilation agents, fillers, and catalysts on the insulation pressure resistance was studied, and finally a powder coating for new energy vehicle power batteries with excellent electrolyte resistance, excellent insulation performance and stable humidity and heat resistance was obtained.

Powder coatings have the characteristics of energy saving, environmental protection, no VOC emissions, good decoration, and safe use.

Weigh the raw materials according to the formula, mix them evenly, and extrude them with a twin-screw extruder.
After cooling and crushing, they are pulverized with a special high-speed grinder and passed through a 180-mesh standard sieve to obtain powder coatings.
The powder coatings obtained are high-voltage electrostatic spraying and curing time 200℃/10min, control the thickness of the paint film to 0.
1~0.
15mm, and then conduct various tests.

1.
4 Test method

The test items, methods and indicators are shown in Table 2.

2 Research content

Due to different raw materials, curing temperature and time, and workpiece pretreatment methods have a greater impact on the insulation performance of the powder coating of aluminum batteries, and the limited space of automobile battery packs, the thickness of the coating for power batteries of new energy vehicles is limited (0.
1~0.
15mm) ), the impurities brought into the production of powder coatings also have a certain impact on the insulation performance.

This paper studies the effects of different types of resins, the amount of curing agent, catalysts and fillers on the insulation voltage resistance, electrical breakdown strength, and electrical breakdown pass rate of the cured coating under a certain thickness.

2.
1 The influence of different epoxy resins on electrical insulation properties

Resin is the most important component of powder coating film-forming material, and its performance must have a significant impact on the insulation performance of the coating.

Bisphenol A epoxy resin has excellent electrical properties, heat resistance, mechanical strength, and chemical resistance.
It is an excellent variety for manufacturing insulating powder coatings.

、，，、、，、、。3。

3，E-12E-12，≥5kV。

，，，，，；

，，，，，。

，A ，，。

，2，，，、、、。

，，，。

2.
2

4，，，，。

。，，。

E-12，，A，，，。

2.
3

。，，，。

5，，，，。，，。

、、，0.
3%~0.
6%。

2.
4

6，，，，。

，。，，，，。

，。，，，。

2.
5

（1）：

7，H，J，I，、、，E-12，H。

I、J，H，IJ，。

(0.
1~0.
15mm)，、、，。

，，8，97%。

，，，，，，；

For the spraying environment of insulating powder, we should also pay attention to protecting the construction environment.
At the same time, we should provide excellent insulating refinish paint to repair the breakdown coating to improve the yield of the customer's aluminum battery shell spraying.

In addition, in the production process of powder coatings, it is inevitable that some metal particles and impurities will be mixed, and it is difficult to obtain a completely pure powder coating, which affects the insulation performance of the powder.

For the production of insulating powder, use special insulating powder production equipment as much as possible, and try to carry out simple and effective metal particle control and impurity treatment to reduce the impact on the performance of the insulating powder.
At the same time, it is necessary to control the baking time to avoid the poor insulation and voltage resistance of the coating due to the incomplete curing of the coating.

3 Conclusion

Insulating powder coatings for new energy vehicles under a certain thickness (0.
1~0.
15mm) require high insulation withstand voltage requirements, so various raw materials must be strictly screened.

Determine the appropriate formula according to the customer's standards, control the mixing of impurities during the production process, and obtain powder coatings with excellent heat resistance, excellent corrosion resistance and excellent electrical insulation properties.
At the same time, a good insulation repair paint with excellent performance should be matched, mainly as follows A few suggestions:

(1) Choose the epoxy resin produced by the two-step method, and at the same time choose the resin with different epoxy equivalents for matching, add an appropriate amount of imidazole catalyst to increase the crosslinking density of the coating, while ensuring the smooth appearance of the coating and ensuring the edges of the workpiece Corner coverage, forming a uniform, complete, continuous, and dense coating;

(2) Choose fillers with small dielectric constant and large resistivity, and at the same time ensure good electrical insulation performance of the coating, and ensure the heat resistance and insulation performance of the coating at relatively high temperatures;

(3) Strictly screen various raw materials, while isolating impurities from the production process, use special insulating powder production equipment to avoid impurities and metal particles that affect the electrical insulation performance of the coating.

Source: Yin Chen, Chengli, Ouyang Jianqun, Liang Yongtian, Guangzhou Kinte Material Technology Co.
, Ltd.
, Guangzhou 510860