On Wed, Jun 07, 2017 at 08:17:13PM +1200, RussellMc wrote:
> Charging NimH to somewhat below max allowed terminal voltage reduces
> oer cycle capacity but greatly increases cycle life. The OLPC people
> claim 2000 cycles from their NimH cells by careful management which
> includes not using the top or bottom 10% of capacity. If he reads
> this far another list member may wish to comment on that :-).

Oh, you mean me!  How nice.  Brain dump.

(a) we didn't end up with NimH in production, because of total weight,
because one of our target countries boasted 45=B0C ambient temperature
for charging, and the price of nickel went through the roof in 2006,

(b) we did test extensively, with hundreds of samples in temperature
controlled ovens,

(c) state of charge range restriction was used, as in the Prius,

(d) we went for LiFePO4 in production until our battery manufacturer
withdrew,

(e) in late 2014 we removed firmware support for NimH so we could fit
in lithium polymer; http://dev.laptop.org/git/users/rsmith/ec-cl4-mmp3/

--=20
James Cameron
http://quozl.netrek.org/
--=20
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