Let'sgoflying!
Touchdown! Greaser!
Can they get a "surface charge"?
How about Li Ion?
How about Li Ion?
nicad battery Q
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gismo
Touchdown! Greaser!
There's a lot I don't know about batteries but I do believe that the term "surface charge" has a lot of different meaning WRT rechargeable batteries. IIRC the original meaning (an increase in the specific gravity of the electrolyte local to the plates) applies only to flooded cell lead acid batteries. I have read of the same term applied to the concept of briefly charging any of the batteries like NiCad and Nimh which exhibit a very flat discharge voltage curve. The purpose of such a charge is to take cells that have been overly discharged to a state where the open cell voltage is close enough to that of a charged cell so the number of cells can be determined by measuring the voltage.
gkainz
Final Approach
Dave, do you mean "memory" instead of surface charge? My understanding is that "surface charge" relates to wet cell batteries (like car and truck batteries) where the measured voltage immediately after a charge cycle is higher than after it sits awhile and the "surface charge" (e.g. +13.8vdc) dissipates, leaving it in a steady state charge (e.g. +12.8vdc).
Memory, I thought was where a battery would rapidly discharge to some "memory state voltage" if you repeatedly discharged down to some point higher than "dead" and then charged up again. For example, discharging your laptop battery down to 80% remaining and then charge up again to 100% repeatedly, used to cause a rapid discharge down to the 80% mark.
I can't recall which battery technology that happened with, and what newer technology overcame that, but I'm sure a quick google would have the capacitance to turn up the answer without resistance. I have to run to a short meeting or I would chase that lead to ground
(groan)
Memory, I thought was where a battery would rapidly discharge to some "memory state voltage" if you repeatedly discharged down to some point higher than "dead" and then charged up again. For example, discharging your laptop battery down to 80% remaining and then charge up again to 100% repeatedly, used to cause a rapid discharge down to the 80% mark.
I can't recall which battery technology that happened with, and what newer technology overcame that, but I'm sure a quick google would have the capacitance to turn up the answer without resistance. I have to run to a short meeting or I would chase that lead to ground
(groan)fgcason
En-Route
Here's an interesting start on the subject:
http://www.batteryuniversity.com/
http://www.batteryuniversity.com/
Let'sgoflying!
Touchdown! Greaser!
Greg- yes. S.C.
Just trying to learn about them more.
I have an old cell phone I think is NiCd, first phone Ive had that lasted longer than the contract (2 years).
Now I take it almost flat and then recharge it. Sometimes it will show a miraculous 3-bar full charge in 5 minutes...just wondered if that term somehow applied. Read a lot online and it seems not. (thanks all for info and links)
Still not sure why it would do this. It doesn't last long so it is an erroneous indication.
Just trying to learn about them more.
I have an old cell phone I think is NiCd, first phone Ive had that lasted longer than the contract (2 years).
Now I take it almost flat and then recharge it. Sometimes it will show a miraculous 3-bar full charge in 5 minutes...just wondered if that term somehow applied. Read a lot online and it seems not. (thanks all for info and links)
Still not sure why it would do this. It doesn't last long so it is an erroneous indication.