# What's the best for my LiON battery **URL:** \ **Category:** Factual Questions\ **Created:** [January 29, 2004, 4:26pm UTC](https://boards.straightdope.com/t/whats-the-best-for-my-lion-battery/226597 "2004-01-29T16:26:59Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![Running\_with\_Scissors](https://avatars.discourse-cdn.com/v4/letter/r/a183cd/32.png) [@Running\_with\_Scissors](https://boards.straightdope.com/u/Running_with_Scissors)\ **Post date:** [January 29, 2004, 4:26pm UTC](https://boards.straightdope.com/t/whats-the-best-for-my-lion-battery/226597/1 "2004-01-29T16:26:59Z")
I have an MP3 player (Creative Nomad Jukebox 3) that uses a Lithium Ion battery. I usually run it off the battery, but occasionally I’m using it in a place with a 120V outlet. As soon as I plug the player in it starts charging the battery. To keep the battery in the best shape, am I better off: 1. Running off the battery until it’s discharged, then plugging it in 2. Running it off the power cord, even though the battery may be only a little discharged, knowing that when I’m done listening the battery will be fully charged again or 3. Removing the battery while I run it off the cord. Your assistance is appreciated. Thanks, Steve ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [January 29, 2004, 4:39pm UTC](https://boards.straightdope.com/t/whats-the-best-for-my-lion-battery/226597/2 "2004-01-29T16:39:50Z")
LiIon batteries don’t have the problems associated with overcharging that plague NiCd and to a lesser extent, NiMH types. You should be alright leaving it plugged in even if the battery isn’t fully discharged. ---
**Author:** ![Running\_with\_Scissors](https://avatars.discourse-cdn.com/v4/letter/r/a183cd/32.png) [@Running\_with\_Scissors](https://boards.straightdope.com/u/Running_with_Scissors)\ **Post date:** [January 29, 2004, 4:45pm UTC](https://boards.straightdope.com/t/whats-the-best-for-my-lion-battery/226597/3 "2004-01-29T16:45:53Z")
Yes, but don’t the batteries lose run time the more they are recharged? ---
**Author:** ![Popup](https://avatars.discourse-cdn.com/v4/letter/p/94ad74/32.png) [@Popup](https://boards.straightdope.com/u/Popup)\ **Post date:** [January 30, 2004, 11:58am UTC](https://boards.straightdope.com/t/whats-the-best-for-my-lion-battery/226597/4 "2004-01-30T11:58:20Z")
Lithium-ion cells behave quite differently from e.g. NiCd cells. As opposed to NiCd, their life-span is very short, and there’s not much that can be done about it. NiCd cells typically last thousands of recharge-cycles, if they’re taken care of, whereas Li-ion cells last a few hundred cycles - but almost independent of how they’re treated! Even properly stored, a three year-old Li-ion cell will only have 50% of its initial capacity. If you use it a lot, it will degrade faster, but not dramatically so. If you’re using it a lot, it’s better to keep it topped up when you can. There’s a nice table at the [wikipedia](http://en.wikipedia.org/wiki/Lithium_ion_battery)): [ul] [li] Unlike nickel based rechargeable batteries (NiCd and NiMH), Li ion batteries should be charged early and often. However, if they are not used for a longer time, they should be brought to a charge level of around 40%. Never use the battery care functions some cellular phones provide for nickel based batteries. (This will deep cycle the batteries.)[/li][li]Li ion batteries should be kept cool. Ideally they are stored in a fridge. However, they should not freeze. Aging will take its toll much faster at high temperatures. Keeping them in burning hot cars can kill lithium ion batteries.[/li][li]Buy Li ion batteries only when needed. Look at the manufacturing date. That is when the ageing process commenced. [/li]When using a notebook computer running from fixed line power over extended periods, it is advisable to remove the battery and store it in a cool place. [/ul]