Re: Li-Ion batteries

In article <rpCdnWUjW42OMSfanZ2dneKdnZydnZ2d@xxxxxxxxx>, Bill Wright wrote:
     Lithium-ion batteries limit self-discharge to less than 5% of the 
original capacity per month when batteries are stored at 20°C.

This is making me wonder if the spec is telling porkies. It might have 
been -10 here, but not -20.

I'd advise being very suspicious of any battery specs, unless they describe
all the conditions in great detail. I once designed something that was
calculated to run all day on a 12V Dryfit battery (lead/acid with a gel or
paste electrolyte) - but it didn't. When I tested these at room temperature
down to a cutoff voltage of 10.5V at about 1A (which I thought was quite
generous of me) I couldn't get any more than 10Ah from a brand new one, and
of course they'd get worse with age.

Rod.

.

Relevant Pages

  • Re: Thoughts on Design time for a switching power supply
    ... from spec to schematic to PCB layout ... The spec is roughly: ... design to use smaller less expensive parts. ... Make sure you get a solid written spec on this one- the battery adds ...
    (sci.electronics.design)
  • Re: Best method for dropping supply voltage a volt or two for low power device?
    ... volts. ... I think 8V is the cranking voltage spec for most apps- definitely not ... 9V-has nothing to do with a dead battery. ... That must have been a 6 volt system, or possibly the voltage at the starter ...
    (sci.electronics.design)
  • Re: Thales Mobile Mapper CE
    ... The system is sold as having an "all day" 8 hour battery life running GPS. ... The spec page gives tha power consumption as 2.4W nominal, ... > It mentions USB host and device ports but nothing about what it can act ... > more you're going to have to splash out on an expensive SD card or swap ...
    (sci.geo.satellite-nav)
  • Re: Battery Charger Design
    ... To design a battery charger, you have to disclose a LOT about ... Spec at the link says it will last 6-years being abused like that. ...
    (sci.electronics.design)
  • Re: Li-Ion batteries
    ... original capacity per month when batteries are stored at 20°C. ... This is making me wonder if the spec is telling porkies. ... I'd advise being very suspicious of any battery specs, ... brand new one at room temperature was quite an awkward discrepancy. ...
    (uk.tech.digital-tv)