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Will using a solar cell fry my batteries? Answered

I intend to use a 6V 50mA solar cell to charge my cell phone and to charge 2 AA batteries separately.
After review of some instructables, Ive read comments about a voltage regulator, capacitors, and the use of a diode but I do not actually see these items in use.  Do I need these things?



Best Answer 8 years ago

Type "solar battery charger" into Google.  Most of the hits on the first page include circuit diagrams.  If you don't know what a particuar component is, the writeup that goes with the schematic should tell you.  For a circuit this simple, you can lay out your components and wires right on top of the schematic and just "connect the dots."

If you're read other questions around charging, you'd have seen people point out that different batteries require different types of charging. You could potentially damage your batteries if you don't do it right.
The phone for one will probably want a regulated supply.


Boy you got me on that!    I never even thought of searching the answer section.
Unfortunately, I am not finding an answer I can work with.

.  Capacitors and diodes are usually for use when converting AC to DC (but you can find diodes in some charging circuits to prevent the charger, such as those that use sunlight, from discharging the battery when output is low).
.  Since your batteries are ~1.5V, you will overcharge the batteries during periods of medium to low light level. Ie, you need, at minimum, a regulator. As lemonie points out, some batteries can be very picky about how they are charged, so you will probably need more than just a regulator.

Unfortunately I first only looked at a couple of instructables that simply put a solar cell to a phone............easy
After more research, it is not that easy and its all stuff I don't know about.   I'd like to learn more but do not know where to start.
You say: at minimum I'd need a regulator........unless I can find an intructable using the same solar cell with a regulator (and part #) I would not know what to do.............so I'll look some more.

.  Oops! "periods of medium to low light level" should be "periods of medium to high light level"