Lithium-ion batteries have a limited life span and are affected by many factors: environment, storage, number of charge/discharge cycles, and degree of discharge/charge.
To extend the life of the battery and the duration of battery use, we recommend following these simple guidelines:
Avoid heat and humidity
The battery is designed to operate optimally at room temperature.
High temperatures can shorten the life of lithium-ion batteries.
Avoid high humidity environments.
It is best to keep the handheld/graphing calculator in a cool, dry place that is as close to room temperature as possible.
Use and recharge
As lithium-ion batteries age, their capacity decreases. With proper care and normal use, the battery should last approximately 3 years.
If the handheld/graphing calculator is used frequently, the battery should be charged frequently. Do not wait until the battery is completely discharged before charging.
If the handheld/graphing calculator is not used frequently, the battery should be fully charged at least once a month.
Do not leave the handheld/graphing calculator connected to a charging device for more than 3 days.
Use only rechargeable lithium-ion batteries specified for use with handhelds/graphing calculators.
Use only charging devices specified for use with handhelds/graphing calculators.
Fully charge the handheld/graphing calculator before testing.
Use and charging
As lithium-ion batteries age, their capacity decreases. With proper care and normal use, the battery should last approximately 3 years.
If the handheld/graphing calculator is used frequently, the battery should be charged frequently. Do not wait until the battery is completely discharged before charging.
If the handheld/graphing calculator is not used frequently, the battery should be fully charged at least once a month.
Do not leave the handheld/graphing calculator connected to a charging device for more than 3 days.
Use only rechargeable lithium-ion batteries specified for use with handhelds/graphing calculators.
Use only charging devices specified for use with handhelds/graphing calculators.
Fully charge the handheld/graphing calculator before testing.
Recommendations for storage for 3 months or longer
The optimal temperature for proper care and storage of lithium-ion batteries is 0–25° C/32–~77° F.
Long-term storage can cause deep discharge of the battery, which may degrade the lithium-ion battery and reduce battery capacity, life, and rechargeability.
Therefore, it is recommended that the battery be fully charged before storing the handheld for an extended period of time and fully charged every three months during storage.
Keep the handheld operating system up to date
Update the handheld/graphing calculator operating system when a new version is available. The new operating system may include new programs to optimize battery life.
