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Universal (adjustable) Rechargeable Battery Power Supply? Answered

I would like to build a battery power supply that has these features:

* holds some number of commonly available alkaline or rechargeable cells (AA or C since those are pretty common)
* has adjustable voltage for 3V-18V (or whatever might be practical)
* has adjustable current 100mA-3A (again, whatever is possible)
* batteries can be recharged by plugging in to normal AC outlet
* can still function as a power supply while charging (perhaps via AC?)

Is such a thing possible?

With phones, iPads and other items that are battery powered, it would be nice to be able to power a few accessories via battery and not need to recharge (i.e., be able to load fresh batteries) if on a remote recording session (for example).

I don't know much about electronics, and would need a higher degree of hand-holding for parts selection and other stuff. I am good with a soldering iron and have done a few DIY projects and kits that have all worked fine.


That's very helpful to know. Thank you.

Sounds like it will make sense to get a different LI-Ion for each device as needed. I very much appreciate your help.

There are already rechargeable LI-ion portable external battery packs on the market. I use them as backup for cellphones/ipod/ipad. The have status lights and are recharged by wall wart or usb. Most devices use 5volts on USB., you may have other equipment that might need some sort of voltage regulator or gang up two or more battery packs to get the right voltage you need. You want to get something that has a max current rating that can supply the power for your device like 2A for a ipad 4th gen. Search for what's out there since it is cheaper to get a pre-built unit unless you want to cobble it on your own. Good luck.

Thanks for the reply. Sounds like a custom and adjustable power supply would be difficult to make and/or expensive.

I have several devices, most need 5v, but there are other important ones with different power needs. I'd like to have a battery pack for each of them. Or at least certain combinations.

The disadvantage of a LI-ion pack is that once its drained, I'd need to recharge. With the ability to insert common alkaline or rechargeable cells I could continue to work "off-grid", say, during a recording or performance by popping in fresh cells.

I guess you would want to plan out the possible usage of these power packs. Li-ion does last noticeably longer than regular alkalines. You would need to lug around "spares for the spares" for what a lithium ion would last.