How do I charge a 3.7V battery from a 1V source?

Question

I am trying to charge a 3.7V Battery using a small solar cell, which has an output of 1V and 2uA due to the operating conditions. I figure i might need a diode, some capacitors and a switching circuit, but I really don't know

Update:

Any ideas on how to store the energy are also very welcome. I need enough energy to power a regular LED for a while

? · Accepted Answer

you put four of them is series.   But it will  take a very long time to charge any battery at 2 microamps.
for example   this battery  cell   1.2 volts  and 3 Ah
ihttp://www.allelectronics.com/item/nmh-sc/ni-mh-sub-c-3000-mah-rechargeable-w/solder-tabs/1.html
it would take  1.5  million hours to  fully charge.  or roughly 342 years.

the average LED  uses 18 ma which is roughly 10000  times what you cell is putting out..

Mr. Un-couth · Answer

With great difficulty.

mike1942-f · Answer

You don't - the source voltage and the power is much too low - any gadgetry that you add will produce more losses and you will never the cell charged. You need a bunch of solar cells to get above the 3.7 volts.

Lee26Caloo秦君子蘭 · Answer

NO HOPE TO RUN ANY BOOTUP CIRCUIT WITH SOURCE CURRENT IS SO LOW AS 2uA !!!
EVEN A SIMPLE CIRCUIT EXISTED IN GARDEN LED LIGHT THAT CONVERTING A SMALL SOLAR CELL POWER INTO 3V WOULD NOT WORK WITH 2uA.

dogsafire · Answer

You stack four of the 1 volt sources in series.
If your cell can only produce 2 uA, you're going to wait a reealllly long time for your battery to charge

Scott · Answer

No can do.

BTW, if a solar cell only has an output of 2uA, it might be worthwhile getting a different solar cell.

How do I charge a 3.7V battery from a 1V source?

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