Phone battery level for prolonged storage

Joe

Since I got my new phone, I am not going to use my old one (BB Bold 9000). Therefore I am going to turn it off and store it in a nice drawer.

My question is: What charge level should I leave the battery in?

In order to avoid battery aging, do I need to store it with full battery? empty battery? I read somewhere 40% charge level is optimal. It may be just rubbish.

Links to articles/publications explaining the subject are greatly appreciated.

Georges

I'd say around 50%.

Sony Vaio laptops have a battery care function which allows you to limit the charging level to 50% to preserve battery and increase its lifetime.

proners

yup 50% e.g. http://www.apple.com/batteries/notebooks.html

Samer99

Question: How does Dell recommend batteries be stored for a long period of time?
Answer: For extended storage (over 21 - 30 days), these guidelines can better preserve the life of your battery:
If it's a new battery, store it in its box until you need it. Otherwise, charge or discharge the battery to 40 - 60% capacity using your Windows operating system power meter, then remove it from your system.
Store in a standard office environment, away from extreme temperatures.
If possible, don't buy batteries until you need them.

http://www.dell.com/content/topics/global.aspx/batteries_sitelet/en/batteries_faq?c=us&l=en&cs=19#faq37

yasamoka

In all the articles I read, 40% is what I found. One article even had the battery tested at those levels at certain temperatures. So it's not rubbish. I will link you to those articles when I get the links.