On 19 Dec 98, at 16:57, Giles wrote:
>
> My experience supports the negative aspects of Ni-Mh batteries. I have had
> experience with two laptop computers with Ni-Mh batteries and the batteries
> do not even last 2 years, even when the computers are run off mains 900f
> the time. Given the incredible cost of these batteries this is not good.
> An HP engineer told me he recommended removing the battery pack at regular
> intervals and shorting it with an appropriate resistor - forget the value -
> to ensure a complete discharge then fully charging the pack and discharging
> it again - perhaps doing this a couple of times! This little proceedure
> was certainly not in the manual!
My experience with about 20 different laptop models over the past 5 years
supports this also - NiMH seemed great on paper, but the results were often
not much better than NiCds, and NiMH were 2-3 times the price. I just
replaced another Toshiba NiMH battery at less than 2 years, for $170 CDN.
> The best technology seems to be rechargeable Lithium Ion batteries -
> negligable self discharge even after a year, high current delivery, NO
> memory effect at all, higher energy density than Ni-Mh or NiCad and I
> believe William indicated they function at low temperatures - or was that
> only the non rechargeable Lithiums?
>
> The only drawback is cost and charging. They are very expensive and
> require a rigorous charging regime - or they go boom. I purchased a Sony
> Li-Ion battery intended for a camcorder - NP-F530. It is a single pack (70
> x 37 x 20mm) and is nominaly rated at 7.2v and 1350mAh. I use this battery
> with a portable DAT player that absolutely eats NiCads. I had to go to
> some lengths to construct a suitable charger for this battery (if anyone
> wants details contact me off list). My experience - absolutely fantastic!
The new Sony Li Ion batteries are fantastic, and seem to have very little self
discharge. On a camcorder, I get 2.5 hours out of a battery the size of two
AAs. (maybe the same pack you mention, or very close).
> Now this may not be directly applicable to OM use but I believe there are
> more conventionaly sized Li-ion batteries available which might be able to
> be used in situations where cost-no-object performance is required.
Rechargable AA lithiums are around $5 here, but I'm not sure what recharger
is needed to safely use these.
Shawn & Janis Wright
swright@xxxxxxxxx
http://Zuiko.sls.bc.ca/~swright
(Olympus List Archives)
< This message was delivered via the Olympus Mailing List >
< For questions, mailto:owner-olympus@xxxxxxxxxxxxxxx >
< Web Page: http://Zuiko.sls.bc.ca/swright/olympuslist.html >
|