Protection Board - 2S 7.4V 3A 18650 Lithium Battery

Hi Guys, I recently bought the below board for a project that Im working on that would have been to charge two 3,4v batteries in series.

the board.

https://www.electromannsa.com/products/2s-7-4v-3a-18650-lithium-battery-protection-board?variant=39525151342774

However with this circuit there are no LED displays to indicate when the batteries are charged, Also something confusing to me is the power output + & - share the same solder points as power input + & - so what will stop the battery from discharging back to the power source once charged.

Anyone have some knowledge on this Id love to hear what you think. Thank you .

by Rhine
November 06, 2021
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1 Answer

Answer by vicmc116

Hi the picture of the board on the website says the input voltage goes to P which is the two solder squares the output voltage B goes to the batteries B being the long strips at the end.

+1 vote
by vicmc116
November 07, 2021

Hi Vicmc thanks for replying and sorry for the late reply. A guy suggested on a facebook group that I use the TP 5100 board which is for two cells and has the led indicators on it.

by Rhine
November 18, 2021
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