Maximizing Battery Life and Lifespan on Dynabook/Toshiba Systems.

Document ID: 4016576


Posted Date: 2019-08-07


Distribution: View Public Website



“Battery life” is the amount of time your device runs before it needs to be recharged. “Battery lifespan” is the amount of time your battery lasts until it needs to be replaced. Maximize both and you’ll get the most out of your devices, no matter which ones you own.


About lithium ion polymer battery characteristics

Inside the lithium ion polymer battery cell, the electrolyte oxidizes and gas is generated as it degrades. Therefore, when the battery cell approaches its life, the battery pack may swell (the battery pack is coated and no gas leaks to the outside). This is a characteristic of lithium ion polymer batteries and there is no safety problem.

Discontinue use of the expanded battery pack and immediately replace it with a new battery pack.

Keep in mind that if the battery pack that has reached the end of its life is not removed from the main unit, it may swell and damage other components.


Avoid extreme ambient temperatures.

Your device is designed to perform well in a wide range of ambient temperatures, with 62° to 72° F (16° to 22° C) as the ideal comfort zone. It’s especially important to avoid exposing your device to ambient temperatures higher than 95° F (35° C), which can permanently damage battery capacity. That is, your battery won’t power your device as long on a given charge. Charging the device in high ambient temperatures can damage it further. Software may limit charging above 80% when the recommended battery temperatures are exceeded. Even storing a battery in a hot environment can damage it irreversibly. When using your device in a very cold environment, you may notice a decrease in battery life, but this condition is temporary. Once the battery’s temperature returns to its normal operating range, its performance will return to normal as well.


How to extend the life of the battery pack when stored for long periods of time.

To charge the battery, wait until the battery level indicator shows about 30%. Also, avoid direct sunlight and charge in a cool, damp place. Refilling with high battery may accelerate battery deterioration and shorten battery pack life.

The lithium ion battery pack included with the product is capable of approximately 300 * 1 charge / discharge cycles. The service life of the battery pack varies depending on the operating environment, but “1 year from the start of use” is a standard, and when it is used repeatedly, it gradually deteriorates and battery capacity decreases. In addition, even if you are not using the battery powered, if you continue to use the AC power supply with the battery attached, deterioration will gradually progress. With the main unit attached, the battery pack is kept at a temperature higher than room temperature (about 40 to 50 ° C) by the main unit heat, which accelerates the deterioration further. Normally, if the storage temperature of the battery pack rises 10 ° C, the rate of degradation will double.

If you do not use the battery for more than 2 weeks or do not use the computer for a long time, removing and storing the battery pack can prevent deterioration and extend the life.

Storage of the battery pack: Remove the battery with 30 to 50% remaining capacity, store it in a cool, dry place away from direct sunlight. Repeated storage near full charge may shorten the life. Store in a plastic bag etc. so that the terminals of the battery pack will not short. Do not store in places exposed to high temperatures. If placed in a place exposed to high temperatures, such as in a summer car, it may cause battery deterioration or malfunction.

The lithium ion battery pack cannot be recharged when the capacity inside the battery cell is completely exhausted (over-discharged). If the battery is stored for a long time, check the remaining battery capacity periodically on a basis of about once every three months, and if it is less than 30%, charge it until it is between 30 and 50%.  

If you remove the battery and use the computer with AC power only, it will turn off as soon as the power is turned off due to a power failure, etc., so it is recommended that you save your work frequently. It is not recommended to install the battery pack on the body continuously, even though the battery pack is not used for UPS application. It may cause battery deterioration or failure.

If lightning starts to stop use immediately or remove AC power and switch to battery power.

Be careful not to apply shock or force to the battery pack. It may cause damage to the battery pack.

※ Instructions for handling and storing the battery pack are also described in the computer manual. Please check the manual of each model.

※ The life of the battery pack changes depending on the operating environment. It does not guarantee the number of charge and discharge cycles.

Export Control and EULA
Use of any software made available for download from this system constitutes your acceptance of the Export Control Terms and the terms in the Dynabook end-user license agreement both of which you can view before downloading any such software.