Lithium-Ion Battery Routine Maintenance and Care for TI Graphing Calculators

Lithium-ion batteries have a limited life, which is affected by several factors: environment, storage, the number of charge/discharge cycles, and level of discharge/charge.

To extend battery lifespan and battery life, we recommend following these simple guidelines:

1. Avoid heat and humidity:
   • Batteries are designed to operate optimally at room temperature.
   • Heat can reduce lithium-ion battery life.
   • High humidity environments should be avoided.
   • Keeping handhelds/graphing calculators in a cool, dry place as close to room temperature as possible is ideal.


2. Usage and Charging:
   • As lithium-ion batteries age, they lose capacity. When properly maintained and under normal usage, batteries are expected to last about 3 years.
   • If you use the handheld/graphing calculator regularly, recharge the battery often. Avoid waiting until it is fully discharged.
   • If you do not use the handheld/graphing calculator regularly, fully recharge the battery at least once per month.
   • Do not leave the handheld/graphing calculator connected to a charging device for longer than 3 days.
   • Use only rechargeable lithium-ion batteries approved for the handheld/graphing calculator.
   • If you are using a wall charger to charge your calculator, make sure you are using the TI wall charger that came with your calculator or other UL-certified USB charger rated for at least 1 amp (usually written as “1A” or “1000 mA”). To determine whether your charger is UL-certified, flip it over to the inside, and read the label. Look for the UL stamp, and confirm that it states that it is 1000 mA or higher.
   • Charge the handheld/graphing calculator fully before tests.
   • If your rechargeable battery is at least 2.5 years old and no longer holding a charge, it may be time to purchase a new TI Rechargeable Battery.
   • If it’s time to replace your battery, you can place an order for a TI Rechargeable Battery through the TI Online Store at https://epsstore.ti.com or by calling 1-800-TI-CARES (1-800-842-2737) Monday through Thursday: 8:00 a.m. – 7:00 p.m. and Friday: 10:00 a.m. – 7:00 p.m. Central Time.


3. Recommendations for storing handhelds/graphing calculators with lithium-ion batteries for 3 months or longer:
   • The best temperature for proper care and storage of lithium-ion batteries is between 0–25° C/32–~77°F.
   • Extended storage can cause batteries to discharge deeply, which can deteriorate the lithium-ion cell and reduce battery capacity, service life, and ability to recharge. It is suggested, therefore, that the battery be fully charged before putting the handheld in extended storage and that it be recharged fully every three months while in storage.


4. Update Handheld Operating System as new updates become available:
   • Update the handheld/graphing calculator OS as new releases become available. OS updates may contain new programs to optimize battery life.

For instructions on how to replace a TI Rechargeable Battery in a Texas Instruments calculator, please select from the links below to find the Getting Started guide for your calculator:

TI-Nspire™ CX II/TI-Nspire™ CX II CAS TI-Nspire™ CX/TI-Nspire™ CX CAS TI-84 Plus CE TI-84 Plus C Silver Edition

Users who experience problems charging handhelds/graphing calculators may contact a TI Customer Service Representative at 1-800-TI-CARES for help resolving problems.