Is there such a thing as a USB LIthium charger?

[Weylan]

I am looking for a USB powered Lithium charger of AA Lithiums, RCR123a, or the AAA sized or smaller lithiums.

Does such a thing exist? I use solar power to generate 6V. So I have about 10ah of 6V available for charging. This is power I can easily and cheaply add more to if I can find a good charger and a need.

I have a 12V Lithium charger that works, but It would be nice to have a 5-6V charger that can do 1 or 2 cells, from say 100-500mah is fine. It does not have to be super quick. I have special chargers for that, but charging that works and shuts off the charge after the battery is full, is a must. Since It is a solar charger that will charge durring the day, the battery may be unattended for hours at a time. (yes, the battery is to be charged in a fire safe location and fire safe jar.)

 

[barkingmad]

Bump...

 

[linterno]

If you like electronics (I guess you do) then you could build your own USB charger. I did it using a MAX1811 chip. Additionally to the MAX1811 you only need a couple of capacitor, a resistor and an LED to build it.

 

[Weylan]

Best I found so far is this from Spark fun electronics which I may just use, but the charging rate is really slow, 100ma.
http://www.sparkfun.com/commerce/product_info.php?products_id=726

So for a 2400mah battery it could take 24 hours. which works, but it is a shame that it will take so long. I am thinking of just pulling a cell phone apart and provide power to the cell phone battery charging circuit to chrage the battery. Most of these chargers charge pretty fast 300mah to 1A given a source that can provide that much power.

I have not used either solution yet.

 

[coppertrail]

I believe I saw one on DealExtreme the other day . . .

 

[65535]

Sanyo has a NiMH charger that runs on USB power, I have never heard of a low power lithium charger, you might look into a boost circuit that could give you 12 volts from 5 volts and it might be a lot more feasable.

 

[kay188]

I believe I saw one on DealExtreme the other day . . .

There ARE usb lithium chargers on deal extreme.