I'm working on a small project and I wanna know what will happen if I plug my phone into a charger with a cable that I cut and soldered again, but soldered the + wire to - and the - to +? will it charge? will it harm my phone / battery? Thanks


closed as off-topic by Chris Stratton, Lorenzo Donati, DoxyLover, Leon Heller, Bence Kaulics Aug 15 '16 at 10:27

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "Questions on the use of electronic devices are off-topic as this site is intended specifically for questions on electronics design." – Chris Stratton, Lorenzo Donati, DoxyLover, Leon Heller, Bence Kaulics
If this question can be reworded to fit the rules in the help center, please edit the question.

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    \$\begingroup\$ There is a small chance that the phone is fitted with reverse voltage protection to avoid such accidents. But if it isn't. then you will destroy your phone. Do you feel lucky? ... \$\endgroup\$ – Brian Drummond Aug 14 '16 at 19:47
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    \$\begingroup\$ ... well, do ya? punk? \$\endgroup\$ – Majenko Aug 14 '16 at 19:58
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    \$\begingroup\$ This is obviously not a good idea, but the question is off topic because there is no basis for knowing how a given finished consumer product - especially one that hasn't even been identified will respond. But naming the phone won't make it on-topic either. \$\endgroup\$ – Chris Stratton Aug 14 '16 at 20:06
  • \$\begingroup\$ It's generally not worth splicing USB cables - hard to do a good, lasting job, and they are so cheap. If you really want to test if you got it right (and yes, it is very hard to apply meter probes to a USB connector without shorting it) test on something cheaper that does not contain a battery pack. \$\endgroup\$ – Chris Stratton Aug 14 '16 at 20:08
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    \$\begingroup\$ Someone upvoted this question?!? Come on! It must be joke vote! Even on the cheapest battery there is written "do not reverse polarity"!!! This is the ABC of the electronic device user. The question doesn't show any research effort and it's usefulness as it stands is highly debatable. I must admit it is crystal clear, though! The next sillier question would be: "if I eat a battery, would it do harm to me?" \$\endgroup\$ – Lorenzo Donati Aug 14 '16 at 22:31

Most components are sensitive to polarity. Reversing the polarity will damage them. Do not reverse the polarity.

  • \$\begingroup\$ Contrary to what star trek will have you believe ;) \$\endgroup\$ – Tom Carpenter Aug 15 '16 at 0:24

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