Palm Treo 700WX User Manual page 385

It's best to replace the battery when it no longer provides acceptable
performance. It can be recharged hundreds of times before it needs replacing.
Don't store the battery in high temperature areas for long periods of time. It's
best to follow these storage rules:
Less than one month:
-4° F to 140° F (-20° C to 60° C)
More than one month:
-4° F to 113° F (-20° C to 45° C)
Disposal of Lithium Ion (Li-Ion) Batteries
To avoid being burned, do not handle a damaged or leaking Li-Ion battery.
For safe disposal options of your Li-Ion batteries, contact your nearest Sprint
authorized service center.
Special Note: Be sure to dispose of your battery properly. In some areas, the
disposal of batteries in household or business trash may be prohibited.
Section 8A: Important Safety Information 369