Stuuuupid question with batteries

[geddiesburg]

Hey all,

So I picked up my palm pre last night. I have what sounds like a freaking dumb question about battery life. It seems everyone has a different opinion on it, the two sales guys at the Bell store actually got into an argument about it. Is it better to drain the battery completely then charge it to full? Or just top it up when needed? I've been told that because it's a lithium ion battery it doesn't have memory, so you can do what you want. Someone else said that when they heat up during charging if it isn't completely drained it loses capacity as it heats up. Can someone please shed some light onto this for me?! Thanks

Edit: Also, does it make a difference if I plug it directly into the wall or charge through touchstone as far as longevity of the charge?

Andrew

 

[TheStu]

A lithium ion battery is supposed to maintain at least 80% of its capacity (so if it starts out as a 1000 mA battery, it will maintain at least 800mA) after 300 cycles. I have heard that anytime you recharge the battery below 50%, that is a cycle. So, if the battery is only a little drained, recharge it, why not. If the battery is past halfway, let it run down as far as you are able and then recharge.

I do not recommend recharging it every night unless you have to, which you might with the Pre. My cell phone goes days between charges, but I have a dumb phone.

 

[Krazy4Real]

Just charge it whenever you want. Lithium ion has no memory effect. I've had my HTC Touch for 2 years now. I charge it every night. If I don't, it still lasts for 2 days with full microsoft exchange direct push, and relatively high call volume and data usage.

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.

 

[pm]

Good guidelines, Krazy. I've been dealing with lithium batteries for year (I have a home-built e-vehicle with a hefty-sized pack) and those are exactly the ones that I have heard as well - all nicely summarized.