Genuine GP (Gold Peak) are reasonably good. They are a Hong Kong
company with manufacturing in mainland China.
But GP is so large and well known in China that \inferior
counterfeited lookalike copies are made.

Another large and competent Chinese maker is BYD. (I'm told Warren B
holds a large shareholding but can't vouch for that).

I have some Sony counterfeits (sold in NZ about 6 years ago) that are
visually indistinguishable from the real thing. They are a reasonably
good quality cell but of significantly lower capacity than claimed and
lower weight. They actually implement a combination of capacities and
model numbers etc that is not quite a match for a real cell - they
upped the claimed capacity while copying. I have the outer cardboard
box and plastic boxes for groups of 4 and these are all also good
copies!. So, other than utterly rigorous inspection may not detetc
fakes.

But, some usually good badge engineered cells and some name brad cells
that are quite possibly genuine are turning up here with lower or much
lower capacities than claimed. I have tested Camelion cells which are
perhaps 2/3 claimed capacity. Camelion  does very well when they do
well - their single cell emergency charger / torch  is far better than
almost anything else I've seen. And even modern Sony batteries have
tested enough below capacity to make me wonder about their provenance.

>From the local auction site I have bought "2400" mAh cells that are
actually 800mAh. The seller has many sales (many products) has  near
100% positive customer feedback.

So - establishing the provenance / genuineness / supply path of your
cells is a necessary step if serious.

___________

Deep deep discharge of NimH shortens life and is not advised and is
easily enough prevented. They do not suffer the reverse polarity
"whiskering" caused by electroplating that NiCd's do but reverse
charging a cell in a string is not at all wise. Occasional balance
charging (slow rate overcharge so all cells MUST be fully charged),
matched cells and not too many in a string is all it usually takes to
keep them honest. As string length increases the delta V variation of
an individual cell can rise while still keeping the total voltage
above a minimum level. To give an extreme case -  10 cells that are
discharged to 1.0 Volt each end point can be 'spoofed" by 9 cells at
1.11 V each and one call at 0.0. Much shorter series strings can
manage this with enough lack of care.



   Russell McMahon
--=20
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