Hi All,
It is "said that" NiCad battery cells usually fail to "short circuit" and that Lithium Ion ones usually fail by just loosing their ability to hold a charge viz they go "open circuit"
Is this true or....?
many thanks
Graham G3VZV
On 11/01/12 12:12, g.shirville@btinternet.com wrote:
Hi All,
It is "said that" NiCad battery cells usually fail to "short circuit" and that Lithium Ion ones usually fail by just loosing their ability to hold a charge viz they go "open circuit"
Is this true or....?
many thanks
Graham G3VZV
It certainly *seems* to be true. We have radios with NiCads that are still struggling on with reduced capacity but when they go, they go dead short across the cell. This is because little whiskers of cadmium eventually grow across the electrolyte.
NiMH doesn't seem to do this, and can otherwise be considered a drop-in replacement for NiCad.
The Lithium Ion batteries we use seem to hold up pretty well until about 600 cycles, then fall off very rapidly.
Hi Graham,
Lithium Ion cells also fail to a short.
But, typical consumer LiIon "batteries" include a safety protection circuit that will disconnect the cell from the battery terminals if the cell voltage drops below the min discharge voltage so it looks like it fails open.
For example: http://datasheet.sii-ic.com/en/battery_protection/S8200A_E.pdf
73, Tony AA2TX ---
On 1/11/2012 7:12 AM, g.shirville@btinternet.com wrote:
Hi All,
It is "said that" NiCad battery cells usually fail to "short circuit" and that Lithium Ion ones usually fail by just loosing their ability to hold a charge viz they go "open circuit"
Is this true or....?
many thanks
Graham G3VZV _______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
participants (3)
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Anthony Monteiro -
g.shirville＠btinternet.com -
Gordon JC Pearce