Maintaining Battery Lifespan

[javaJake]

We will be selling spares and probably an optional 5000mah battery.

This brings up a good question that I asked before, but got mixed answers. This will be the last time I ask.

If someone were paranoid about the battery getting misused and slowly dying, how would that person max out the battery's overall lifespan? As far as I know, the best practice is to charge only when depleted, and discharge all the way after that.

 

[atomicthumbs]

Full charge, full discharge wil lmake it marginally longer-living.

Edit: or just use one of these magickal stickers

 

[deathterrapin]

That's for NiCd and NiMH. Li-Ion is quite the opposite, fully discharging them often will reduce their lifespan.

 

[ruckage]

That's for NiCd and NiMH. Li-Ion is quite the opposite, fully discharging them often will reduce their lifespan.

I was just about to say exactly the same. I found this on the wikipedia which might be what you're looking for.

QUOTE
Guidelines for prolonging Li-ion battery life

* Unlike Ni-Cd batteries, lithium-ion batteries should be charged early and often. However, if they are not used for a long time, they should be brought to a charge level of around 40% - 60%. Lithium-ion batteries should not be frequently fully discharged and recharged ("deep-cycled") like Ni-Cd batteries, but this is necessary after about every 30th recharge to recalibrate any external electronic "fuel gauge" (e.g. State Of Charge meter). This prevents the fuel gauge from showing an incorrect battery charge.[14]
* Lithium-ion batteries should never be depleted to below their minimum voltage, 2.4v to 3.0v per cell.
* Li-ion batteries should be kept cool. Ideally they are stored in a refrigerator. Aging will take its toll much faster at high temperatures. The high temperatures found in cars cause lithium-ion batteries to degrade rapidly.
* According to one book,[34] lithium-ion batteries should not be frozen (most lithium-ion battery electrolytes freeze at approximately −40 °C; however, this is much colder than the lowest temperature reached by household freezers).
* Li-ion batteries should be bought only when needed, because the aging process begins as soon as the battery is manufactured.[14]
* When using a notebook computer running from fixed line power over extended periods, the battery should be removed,[35] and stored in a cool place so that it is not affected by the heat produced by the computer.

 

[Squidge]

You should never completely discharge a Li-ion battery as it can damage the battery. Li-ion batteries do not suffer the "memory effect".

Instead, top up the battery regularly (eg. at night if you use it during the day) and don't let the battery get too hot (preferably less than 25c, so don't store in a hot car for example).

If your buying a spare, don't store it at full capacity or discharged (about 50% is good), and don't store it for more than 3 months without use (preferably you should use it two to four times a month).

 

[Chip]

Technically, Pandora (and nearly all similar handheld devices) uses a Lithium Polymer battery. It's an offshoot of standard Li-Ion technology - Similar, but with some quirks.

RC airplane enthusists have been working with large, custom Li-Po battery packs for years. If you really want to know all there is to know about the care and feeding of Li-Po batteries, go see what they have to say.

 

[Squidge]

So, a question for MJW - Is Pandora charging circuits made for Li-ion or Li-poly? I've assumed the former upto now (Unless of course both are the charged the same way - I have very little knowledge of Li-po batteries).