I have used both Nimh and LiIons, I have to say LiIons are better performer.
LiIons do not lose power much when not used while Nimh lose 1.5%-3% daily. A
nice feature on Sony F-series is you can see how many minutes you have left
on the battery. I am sure other brands using LiIons can implement this
without much trouble, but I doubt you can ever do this with Nimh, they just
don't communicate with cameras much.
Although you can get LiIons from ebay for $15-$25 apiece and that sounds
reasonable, Nimh is way cheaper and easier to get, you are absolutely right
about it.

"Alfred Molon" wrote in message
news.com...
In article ,
says...
Put your nimh idle for 2 weeks and then check how much power it has
left,
and do the same with BP-511, you will see the difference. Then there is
charging time for flashes, memory effect, how accurate camera can detect
the
power level left in batteries. Nihm may be cheaper, but defenitely not
the
top performer.


The memory effect for NiMH is very moderate; charging time for flashes
should be low, as NiMHs can deliver high currents (not sure how LiIons
perform under very heavy load. Concerning the storage, just recharge the
batteries after a long idle period of time.

Advantages of AA NiMH:
- widely available everywhere; in case of emergency you can even run
your camera with standard non-rechargeable AA batteries
- low cost
- no risk the proprietary battery won't be manufactured anymore one day
--

Alfred Molon
------------------------------
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