2s Lipo battery pack diy

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devryd
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2s Lipo battery pack diy

Hi
i am currently working on a 2s 18650 battery pack with 5V in and output and a bms that covers balance charging. Do you have any suggestions for a board or boards that cover these features in a small form factor. I want to put this in an original gameboy case as a retro console

Catnap
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You could use a simple tp4056 board with built in bms. 1s2p configuration, then boost voltage to 5v. The problem is that most step up or down converters have significant quiescent power consumption. Always active 5v is difficult to implement.

devryd
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I found boards with this chip on amazon. The problem is, they only charge with 1A. Can I simply use more of them in parallel to get faster charging?

northqld38
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just to clarify, originally you said a 2s pack. A tp4056 will only charge a single cell so it wont work with a 2s pack.

Your looking to run 2s so you get 8.4v max, 6v min?

One of these would work to protect the cells and balance them https://www.aliexpress.com/item/1005001727331980.html

To charge the pack you just need 8.4v so any generic dc dc buck boost step down reg would work, set it to 8.4v, connect direct to the battery and monitor the voltage once its at 8.4 you can disconnect the charger. Alternativly you can get 2s chargers designed for rc cars etc.

You need to be careful doing this stuff ive shorted packs before during building and had to run them outside so i dont set the house on fire lol.

anyway hope this helps maybe not.

devryd
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This does help, but the circuit is pretty bulky… I would also need a step up converter, to get to the 8.4Volts which increases the size more. I think I will just go with what Catnap said and use a 2p pack and a dc dc step up board