How to take care of L-Ion Batteries?

[Fulmar]

LiIon and LiPo batteries do not have a "memory" and therefore do not require cycling (discharging until nearly dead then recharging until full) - in fact, cycling is a practice that will degrade LiIon batteries. Cycling a battery is something recommended for Nickel Cadmium/NiCad or Nickel Metal Hydride/NiMH batteries which do have a "memory".
If you really want to optimize the life of a LiIon batt, then never fully charge it and never fully discharge it. Heat is another battery killer so keeping it at a cooler temp will prolong the life. Recommended storage conditions are 50-60% charged and stored in the refrigerator (not freezer). So if you leave your laptop plugged in to AC power, pull the batt when it is around 60% charged and put it in the fridge until needed.

With laptops especially, every few charges it best to drain the battery down.  Not for the benefit of the chemistry of lithium ion, but to keep the battery meter calibrated with the computer.  See my earlier post.

The refrigerator trick is HIGHLY overrated.  Taken from Cadex's site (they design high end battery testing and maintaining equipment.


Note the 2% difference is storing the battery at 0C (32F) as compared to room temp of 25C (77F).  I'd rather not save the 2% capacity loss and risk keeping the battery in a generally high moisture environment.  Those plastic battery cases are not air tight and I'd rather not have the potential of moisture getting to the cylindrical lithium ion cells inside.

[stran]

Hey OP, with the Iphone 3g you can easily replace the battery yourself. it has been done by many people including myself, and it only takes about 15 minutes. no soldering required for the 3g.

http://www.iphonebatteryrepair.com/iPhone-3G-Installation-Whitepaper-s/39.htm

[OOZ662]

I know, thanks though.

[WpnX]

With laptops especially, every few charges it best to drain the battery down.  Not for the benefit of the chemistry of lithium ion, but to keep the battery meter calibrated with the computer.  See my earlier post.

The refrigerator trick is HIGHLY overrated.  Taken from Cadex's site (they design high end battery testing and maintaining equipment.
(Image removed from quote.)

Note the 2% difference is storing the battery at 0C (32F) as compared to room temp of 25C (77F).  I'd rather not save the 2% capacity loss and risk keeping the battery in a generally high moisture environment.  Those plastic battery cases are not air tight and I'd rather not have the potential of moisture getting to the cylindrical lithium ion cells inside.

Fulmar,
Let's post the full article written by Mr. Isidor Buchmann / founder and CEO of Cadex where he actually recommends storage of LiIon laptop batteries in the refrigerator. This way people can make their own informed decision on the best way to prolong the life of LiIon batts.
Full article:
http://batteryuniversity.com/parttwo-34.htm

Simple Guidelines


Avoid frequent full discharges because this puts additional strain on the battery. Several partial discharges with frequent recharges are better for lithium-ion than one deep one. Recharging a partially charged lithium-ion does not cause harm because there is no memory. (In this respect, lithium-ion differs from nickel-based batteries.) Short battery life in a laptop is mainly cause by heat rather than charge / discharge patterns.


Batteries with fuel gauge (laptops) should be calibrated by applying a deliberate full discharge once every 30 charges. Running the pack down in the equipment does this. If ignored, the fuel gauge will become increasingly less accurate and in some cases cut off the device prematurely.


Keep the lithium-ion battery cool. Avoid a hot car. For prolonged storage, keep the battery at a 40% charge level.


Consider removing the battery from a laptop when running on fixed power. (Some laptop manufacturers are concerned about dust and moisture accumulating inside the battery casing.)


Avoid purchasing spare lithium-ion batteries for later use. Observe manufacturing dates. Do not buy old stock, even if sold at clearance prices.


If you have a spare lithium-ion battery, use one to the fullest and keep the other cool by placing it in the refrigerator. Do not freeze the battery. For best results, store the battery at 40% state-of-charge.

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Created: February 2003, Last edited: September 2006



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About the Author
Isidor Buchmann is the founder and CEO of Cadex Electronics Inc., in Vancouver BC. Mr. Buchmann has a background in radio communications and has studied the behavior of rechargeable batteries in practical, everyday applications for two decades. Award winning author of many articles and books on batteries, Mr. Buchmann has delivered technical papers around the world.
Cadex Electronics is a manufacturer of advanced battery chargers, battery analyzers and PC software. For product information please visit www.cadex.com.

[Fulmar]

I pulled that graph from their site.  Really worth the 2% storage capacity?  And that's if you're not using the battery for a year.  Again, 98% at 0C amd 96% at 25C.  Unless you're using your laptop as a desktop, it's really not necessary.

And out of the 4 vendors and manufacturers that Batteries Plus uses for laptop batteries, none of them recommend any type of storage outside of standard room temperatures.  Neither Battery Biz, Dantona, Fedco or Ascent.  In fact, storing them in the refrigerator would negate their warranties.

As much as I love Cadex as a corporation for some of their fantastic equipment, I've never agreed with them on this article.