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this is my first time asked on stack exchange, please bear bare with me. Anyway, I created portable monitor using multiple TP4056 as battery charger & protection circuit. But I'm not sure it's safe or not.

this is the wiring diagram : enter image description here

enter image description here

why I wired this way? Apparently the monitor needs more than 5 Watt, and using 1 TP4056 can't give enough power. (the monitor needs 12 volt). So far my solution works, but I worried about the safety.

what I'm asking is this solution safe?

Thank you

edit 2: To power up 12 volt monitor, I stepped up the output from TP 4056 (from around 3-4 volt) using XL6009 module to 12 volt. As you can see, the module located under the batteries.

vein sekundes
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    +1 for saying `please bear with me` .... most people say "bare with me" .... lol – jsotola May 12 '18 at 05:11
  • lol... my bad XD. I want to say English is not my native language, but it's just an excuse. – vein sekundes May 12 '18 at 07:03
  • I'm surprised it works if the monitor needs 12 V. In the absence of external power you'll only get about 4.3 V from the batteries. It looks perfectly safe though. – Finbarr May 12 '18 at 11:15
  • TP4056 has a cut-off at 2.5V, which is rather low. 3-3.3V is best. I’ve also observed TP4056 cutting power at too high load (don’t know the exact ampere value). A LVCO of 2.5V is not going to give you 1000-1200 charge cycles. 5W is a stretch for XL6009, mine can only go up to 4-5W. Does the XL6009 get hot? – user2497 May 14 '18 at 15:01
  • the XL6009 modile is geeting hot, but not that bad (my smartphone is way hotter sometimes). actually from my test, the power consumption around 6 watt (5.12v for 1.14A) . and sometimes spike to 7.2 watt (5.14v for 1.4A). I already tried using 1 TP4056, but it doesen't provide enough power (the screen turned on-off) . I tried using DIY powerbank circuit, it had same problem. – vein sekundes May 17 '18 at 03:43
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    how do you charge the batteries?, you plug a usb to each usb female inputs?, or do you wired them in parallel?, how? – Joe Cabezas Mar 31 '19 at 04:34
  • i linked all TP4056 charging together, so i just need plugin regular charger to one port. – vein sekundes Apr 01 '19 at 05:07

1 Answers1

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The cutoff voltage is a trade-off between maximum current capability and battery under-voltage protection, at high currents (which is your case) the battery voltage can drop down to 2.5V even the battery is not over-discharged but this wasn't your question

There is nothing that forbids you to use this configuration, I actually used-it for a two batteries / two TP4056 configuration.

Dorian
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