Are Cheap Power Tool Batteries Safe to Use? Teardown Test!【Just Buy official Battery】

Published at : 23 Dec 2025

Correction: Later I found an NTC thermistor on the back side of the circuit board. It detects overheating and activates protection. I didn't see it at the time of filming.
Supplement: The monitored voltage is of 1 cell individually and all 5 cells combined. The battery doesn't monitor the voltage of the remaining 4 cells individually. This may cause overcharging.

I do not recommend using any batteries other than genuine batteries. The genuine battery I disassembled in the video is sold at overseas branches of Makita.

Warehouse burned down because of a compatible lithium ion battery → https://youtu.be/s19ZI4tN12c
The National Institute of Technology and Evaluation (NITE) → https://www.nite.go.jp/jiko/chuikanki/poster/kaden/20012301.html

★ Products used in this video (includes an affiliate link)
Makita genuine battery 18 V https://amzn.to/3TkPogQ

If you’d like to get something from AliExpress, it would really help me out if you used this link!
I’ll use any affiliate earnings to help keep my projects going.
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00:00 Introduction
01:37 Disassemble Genuine Battery
04:05 Disassemble Compatible Battery (Company A)
07:45 Disassemble Compatible Battery (Company B)
10:14 Conclusion

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