Rechargeable AA Lithium Batteries

[William_H]

Now I have never seen until now lithium rechargeable batteries with buck converter to give 1.5 volts. Might be a good thing. However beware a lithium rechargeable known as 14250 is the same size as AA battery but 3.7 to 4 volts. No buck converter so could be destructive if fitted by mistake.
These and 18650 can be charged using a cheap charge controller off 5v input. You might find them described as solar charge controller.
I found my local hardware chain (bunnings) carry replacement 18650 and14250 cells for garden solar lights. The 18650 at 2200 MaH seem on test to make that figure. (indeed 12 of them make up the battery for my boat) Unlike Ebay Chinese Ultrafire claiming 10000maH and delivering maybe 100. ol'will

 

[GHA]

Unlike Ebay Chinese Ultrafire claiming 10000maH and delivering maybe 100. ol'will

Worth noting Utrafire are one of the top brands, which is why there are so many fakes. If it's cheap it's fake. Prices of real ones on ali express seem pretty similar to europe

 

[doug748]

useful stuff here from Project Farm:

.