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I want to power my Raspberry Pi 3 model B+ using a battery. It turned on and worked perfectly with:

1) a 5V 1A powerbank or adapters

2) and a 5.5V(4.2+1.3) battery connected directly.

However, i was not lucky in getting it to work with two lithium ion batteries in series 8.4V by either linear and switch regulator of 5V output. For linear regulator, i used 7805 and for switching regulator i used LM2596.

i have tried many variations of the 7805 linear regulator circuits and using different components and testing with multimeter but it did not work with raspberry pi. The same results with the LM2596. I tried both by powering using the USB micro port and the two 5V and GND pins The micro USB cable is perfectly fine as i tried it with powerbank and adapters which worked.

Everything in my project worked fine with these regulators, arduino, lights, motors, sensors except raspberry pi. I tried to make it work separately, i thought maybe the other components are intefering with it, but it still not working. Either power it directly using 5V batteries, or use powerbank or adapters. Its a dilemma because i tried everything i could think of.

Many people recommended this online and it worked for them. Could it be because of the new raspberry pi 3 B+ which has some changes. Please help, i will appreciate it very much.


In the commments, i was told that there could be not enough current being supplied by the regulators. That is true, not enough current is supplied. Thank you for letting me know. I tried the circuit below in an effort to solve my problem. Here i used a TIP142 transistor and a zener diode of 5.6V. I got a voltage of around 5.5V across the emitter capacitor. It worked! It powered the raspberry pi and got the remote desktop and shut it down.

However, i saw a white smoke, i thought im hallucinating, maybe a signal from my brain to take a smoke break, but the zener diode was getting hot. And to be honest the potentionmeter could be replaced with a tiny ohm resistor, cause i spinned it all the way to almost zero resistance. Thats how i got the maximum current. Please can you advice me on how to improve this circuit, so that the zener diode cannot get very hot. Or if you know a way to get high current, please do share. Thank you very much for your time.

enter image description here

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closed as unclear what you're asking by Chris Stratton, Sparky256, Dmitry Grigoryev, pipe, awjlogan Oct 30 '18 at 12:31

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • \$\begingroup\$ The Raspberry Pi uses 2 amps of current and the LM7805 has a limit of 1 amp. The LM2596 should work if the current limit is set for max current. With add-ons like fans, relay board and LCD the Pi can consume close to 3 amps. \$\endgroup\$ – Sparky256 Oct 27 '18 at 3:34
  • \$\begingroup\$ The difference between the 3B and 3B+ is that the 3B+ has dual band WiFi, both 2.4GHZ and 5GHZ bands, and a separate WiFi / Bluetooth controller. Else they are identical and use the same Raspbian OS and Linux core. \$\endgroup\$ – Sparky256 Oct 27 '18 at 4:24
  • \$\begingroup\$ Thank you Sparky256, yes both the 7805 and LM2596 gave around 1.3A. I think the booting sequence uses high current at the begginning. I edited my question and put a circuit that worked but was getting hot and it supplies around 1.47A which worked for raspberry pi. Check it out, if you got any ideas, please letting me know. Thank you for your answer \$\endgroup\$ – Ibrahim Oct 27 '18 at 5:32
  • \$\begingroup\$ So change the 7805 & LM2596 for better ones, just need to look in suppliers catalogues for the specifications... \$\endgroup\$ – Solar Mike Oct 27 '18 at 6:04
  • \$\begingroup\$ Yes, i will order a better regulator with high current to supply. It takes a while and project due soon. Meanwhile will focus on other things as i wait. Thank you Mike, this is a better way. \$\endgroup\$ – Ibrahim Oct 27 '18 at 6:15
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LM2596 runs quite hot at 2.5A, I went with a more powerful "5A" XL4015 module that only gets warm when delivering 2.5A the price diference is only a few cents.

Set to 5V before connecting the Raspberry pi (you'll need a voltmeter)

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