One of our products uses a CR2354 as ram backup for an MC68332 processor, to save cal tables and such. We've shipped over 3000 units, for about 10 years. We pulled the batteries from various RMA units and discharged/datalogged them to determine remaining mah capacity. There was no correlation between age and remaining charge. In fact, the best few batteries were among the oldest.
John
of 0.1mm.
now that is useful information. thanks.
I think you really need to impress by us by saying the C of the oldest batteries actually increased by 25% over time of installation...
Do you have any idea what percentage of its life the individual units were powered up? I've heard people bitch because five year old battery backed 2K * 8 static RAM modules were dead, and had never been used. They couldn't grasp the fact that the battery was only used during power down situations, no matter how small the difference in load current was, when compared to the battery's internal leakage current.
Why should he? Lying is your specialty, Fred.
NASA won't use them in space, either. We had to use 'CapStore' RAM for the equipment we built for the ISS.
I can pick up a year's supply for the computer project for $5 at the flea market, while I'm buying fresh vegetables. :)
John Larkin wrote in news: snipped-for-privacy@4ax.com:
relatively to WHAT?
These are megabuck NMR systems the often run 24/7 for weeks or months, so I'd guess that they were on a good fraction of the time. Still, the batteries didn't show any sign of self-discharge. There was no charging current when powered up.
John
I reported what we measured. I don't need to do anything else.
John
Many other battery technologies.
I wasn't saying the batteries were charged while the equipment was on, just that the battery had less, or no load when the equipment was on, allowing closer to the OEM's specified shelf life.
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