Has anybody tried this?
Might be good for appliances that benefit from the full 1.5V (torches/flashlights as bright as with Alkalines but 1000x rechargeable as NiMH batteries). Only 1200mAh though - the USB connector occupies some space that could be used by the lithium stuff.

Cool ! I might have to try them !

I think the low self discharge MHs have higher value and at the end are cheaper.

You can not use these virtually in anything else than torches or some toys. The problem would be in the output filtration (the lack of it in that crammed space) what will cause problems with any form of radio device...
Plus no indication about the charge state (the electronically regulated output stays constant till it suddenly drops when reaching end of discharge threshold).

These 1.5V/2800mAh rechargeable lithium AA batteries look probably better but they still use "precise voltage conversion technology to make the lithium batteries' voltage change from 3.7V into the output voltage of 1.5V".

Non-rechargeable Lithium AA batteries also exist. I got Energizers (as seen in the attachment) together with a camera purchased in 2008 and didn't use them until recently. Their voltage is more like ~1.85V - making my alarm clock display look a little over-contrasted. Not sure how they lower the lithium voltage.

I think cameras etc. will actually like the 1.5V (regulated till the end of useful charge) batteries much better than 1.2V

(While at that, i am scratching head over why to date camera manufacturers dont set the low battery detection thresholds according to NiMH, but still to Alkalines, in most cameras where this cannot be set in the user menu. Do they think that most users use Alkalines ?)

The only type of battery I used in those kindof cameras was alkalines simply due to the fact that alkalines seem to last longer.