Electronics, Lighting, & Gadgets - Lithium cells versus NiMH cells: photo comparison

For those who find this type of thing interesting, here are animated .GIFs showing a couple blinkies projected on a wall, using both NiMH and lithium cells. Lithium has a higher voltage and tends to hold it high until it finally drops dead, thus the higher light output on these unregulated lights. NiMH, of course, is rechargeable and therefore less expensive.

http://i240.photobucket.com/albums/ff237/mechBgon/BRT-5_battery_comparison.gif

http://i240.photobucket.com/albums/ff237/mechBgon/CB_battery_comparison.gif

The #1 thing to do, of course, is to check your light's aim to ensure that the strong part of the beam is aimed where it counts. Beyond that, if your light gets good runtime on a set of cells, and if you don't mind using non-rechargables to get a little more light output, the lithium cells are an option.

You can clearly see the difference but I don't like the environmental aspects of non-rechargables and also don't want to have to keep buying batteries. However next year I will be running a dinotte light so the PBSF will be a secondary!

They have rechargeable lithium batteries (not AA) and they have AA lithium batteries (not rechargeable). Why can't they make rechargeable AA lithium batteries?

Off topic: I understand there are a couple of new technologies in the pipeline that will blow away existing rechargeable batteries. I can't wait.

They have rechargeable lithium batteries (not AA) and they have AA lithium batteries (not rechargeable). Why can't they make rechargeable AA lithium batteries?

The rechargeable Lithium ION chemistry is totally different from that of Lithium primary cells, just as the chemistry of AA primaries is different from that of rechargables. It is also why the voltage is so different 1.5V (more or less) vs 3.6V for Lithium ION. It could probably be done, but the expense might prohibit it.

BTW, a 14500 Lithium (ION) cell is the same shape and size as an AA cell, it is not 1.2/1.5V though.

The rechargeable Lithium ION chemistry is totally different from that of Lithium primary cells, just as the chemistry of AA primaries is different from that of rechargables. It is also why the voltage is so different 1.5V (more or less) vs 3.6V for Lithium ION. It could probably be done, but the expense might prohibit it.

BTW, a 14500 Lithium (ION) cell is the same shape and size as an AA cell, it is not 1.2/1.5V though.

Ahh! Two different technologies then. That makes sense.

I still can't wait for something better. Even my best rechargeable AAs don't last long enough or provide enough power to work on my commuting headlight.

Arrrg! Love when the 'new and improved' forum eats a reply.

Not enough power for one way or round trip? You can build and buy packs with more capacity for most lights. There are lots of larger cells than AA.

Arrrg! Love when the 'new and improved' forum eats a reply.

Not enough power for one way or round trip? You can build and buy packs with more capacity for most lights. There are lots of larger cells than AA.
Yeah, I know. I'm using 18650s for the commute now. But that's the only use I have for them. We use AAs all over the house. It would be nice to have something more universal.

Yeah, it would be quite an exciting animated .GIF if I had two 10440 Li-ion rechargables in there. That would be 7.4 volts in a ~3V light.

BTW per Eveready data sheets and application manuals the Lithium AA and AAA batteries have MUCH better cold weather capacity than either NIMH or Alkaline cells. By -4F (-20C) both NIMH and Alkalines are down to 20% of normal temperature capacity or less.