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cmnorton
February 8th, 2009, 09:22 PM
I have heard but never confirmed that your battery level should never drop below a certain percentage, or it will be damaged.

What are normal battery use guidelines?

I have a big 8 cell batter for my gazelle ultra. Its at 63% now. Down to which level can I safely run the battery?

jdb
February 9th, 2009, 12:43 AM
I have heard but never confirmed that your battery level should never drop below a certain percentage, or it will be damaged.

What are normal battery use guidelines?

I have a big 8 cell batter for my gazelle ultra. Its at 63% now. Down to which level can I safely run the battery?

There is internal protection in the battery that won't let it drop that low.

jdb

thomasaaron
February 9th, 2009, 04:51 PM
In addition to JDB's comment, letting the battery drop all the way down (as low as the internal protections will allow) doesn't so much *damage* the battery as it does wear it out prematurely. Every once in a while isn't a problem. But habitually running it all the way down has a cumulative effect on the battery's ultimate lifespan.

cmnorton
February 9th, 2009, 10:05 PM
Is 20% a safe place to stop? If not, 1/3, 40%?

This is a gazelle ultra 8-cell.

thomasaaron
February 9th, 2009, 10:14 PM
From what I understand, down to about 25% is a good place to stop. And again, we're all gonna run them all the way down occasionally.

jpoRS
February 10th, 2009, 12:36 AM
Not to thread-jack, but I had always been told that if you don't run batteries down all the way, they develop a "memory" point and never recharge properly. So that is bunk apparently?

Thanks,
jim

jdb
February 10th, 2009, 01:08 AM
Not to thread-jack, but I had always been told that if you don't run batteries down all the way, they develop a "memory" point and never recharge properly. So that is bunk apparently?

Thanks,
jim

It's true, but for a different kind of batteries.

NiCads (Nickle Cadmium batteries) which used to be the universal rechargeable battery suffered from that problem.

Li-ion (Lithium Ion batteries) are more popular now and almost exclusively what are found in laptops.

They hold more energy than Nicads and don't have a charge memory.
They are more particular about the way they are charged and most have some pretty sophisticated circuitry built in.
They've been known to vent flames when not charged properly.

jdb

Gramps
February 10th, 2009, 01:27 AM
There is a lot of good battery information here http://www.batteryuniversity.com/

jpoRS
February 10th, 2009, 05:32 AM
Hmm. The more you know.

Thanks guys,
jim