Copyright: Copyright (C) IBM Corp. 2001,2003.


Tips for Maximizing Your Battery Life

Your ThinkPad battery is a "Consumable" product that decreases in performance over time.  However, there are several things that you can do to improve the performance and life of your battery.

Here are some tips to help maximize your battery life:

1. If your battery is left out of the system for a long period of time without charging, or if the system is not plugged in for several months, it will take longer to charge.

2. Make sure that you are using the correct AC adapter for your ThinkPad model.  Using the incorrect adapter will prevent the battery from charging fully, and will cause the battery meter to display incorrect battery information.

Using the proper AC adapter

3. Recondition your battery by letting your battery run to less than 3% at least once a month. Reconditioning the battery can restore some of your battery capacity.

Reconditioning The Battery

4. When the computer uses a large amount of electricity from the battery (for example, for intensive calculations or high-end graphics applications), the temperature of the battery and the computer may rise.  In this case, the battery might automatically stop charging to so that the battery operates at a level that ensures comfortable usage and normal battery life.  If the battery has stopped charging, it might not start charging immediately when you plug in the AC adapter or it may take more time to completely charge. When the battery is restored to its normal temperature, the battery will start to recharge.

5. Do not place your battery or your ThinkPad in a high temperature environment, such as a car on a hot day.

6. Battery performance will be temporarily degraded if the battery is used in a cold environment.

7. When you store your battery outside of your ThinkPad Computer, store it with a charge of less than 50% to reduce the battery wear.

Battery Characteristics

Reconditioning The Battery

Checking Battery Status

TradeMarks and Service Marks


Battery Characteristics

Batteries are a "consumable" product and battery life decreases over time, depending on how the battery is used.  Over time, the Full Charge Capacity, or total amount of charge the battery will accept, become less than the Design Capacity, or the amount of charge that a new battery can store.  Both of these are measured in Watt-hours (Wh) and are displayed in the Battery Information window.

Normal deterioration

Under average usage patterns (see figure) your ThinkPad battery maintains approximately 70% of its power capacity for the first year of operation.  Average usage is defined as the number of recharge cycles.  A cycle is defined as each time the battery discharges a total of 85% or more and is recharged it counts as one cycle.  The battery health utility uses Design Capacity, Full Charge Capacity, Cycle count and the normal aging properties of your battery to determine your battery capacity status.

X axis	: Year

Y axis 	: Percentage (%) - Full Charge Capacity / Design Capacity x 100

Using the proper AC adapter

Use the proper AC adapter for your ThinkPad computer. There are several types of AC adapters for ThinkPad, 56 watt or 72 watt. If insufficient power is supplied to your battery,  the full charge capacity will appear to be reduced.


Reconditioning The Battery

Reconditioning your battery can increase the full charge capacity of your battery.  It is recommended that you let the battery run to less than 3% at least once a month.

Occasionally, it may be necessary to "deep cycle" your battery one to three times to give it optimum performance.  This will require you to let your battery run completely down, and then to recharge it fully. It is recommended that you charge your ThinkPad overnight for a full charge from a deep recharge condition without leaving your ThinkPad powered on.  A brand new battery should be fully charged overnight before its first use.

To do this, perform the following steps:

1. Make sure you have saved all of your data, and close all programs.

2. Disable Power Management timer settings so that your ThinkPad keeps working during reconditioning the battery.

To disable power management timers in Windows 95 operating systems:

a.  Click Start -> Settings -> Control Panel;  then click Power.

b.  Click  Power Mode.

c.  Select Battery for Power Source if the battery is Li-Ion.

     Select AC for Power Source if the battery is  NiMH.

d.  Record your current power management settings.  After reconditioning your battery, you might want to restore these settings.

e.  Select Customized power mode.

f.  Disable timers by setting each timer to 0.

To disable power management timers in Windows NT operating systems:

a.  Click Start -> Program -> ThinkPad -> ThinkPad Utilities; then click ThinkPad Configuration.

b.  Click Power Management; then click Power mode settings.

c.  Select Battery for Power Source if the battery is Li-Ion.

     Select AC for Power Source if the battery is  NiMH.

d.  Record your current power management settings.  After reconditioning your battery, you might want to restore these settings.

e.  Select Customized power mode.

f.  Disable timers by setting each timer to 0.

3. Determine your battery chemistry.  It will either be Li-Ion or NiMH.

4. Let the battery totally discharge, then let the battery charge.

Perform the following steps if your battery is Li-Ion:

a. Unplug the AC adapter and let the battery totally discharge. The computer automatically goes to standby mode when the battery is fully discharged.

b. With the proper AC adapter, let charge the battery until Battery LED is solid green.

Perform the following steps if your battery is NiMH:

a. Plug in the proper AC adapter .

b. Click Start Refresh button in the Battery Health dialog to start reconditioning your battery. Battery starts discharging. When battery is fully discharged, it will start charging automatically.

c. When the battery LED is solid green, the charge is completed.


Checking Battery Status

You can check your battery health status in the Battery Health dialog. If the battery health status indicator is red, it may be necessary for you to obtain a new battery. If your battery is still under warranty, IBM will provide one to you at no additional cost. If not,  you can purchase a new battery via the IBM Web site at http://www.ibm.com.


Trademarks and Service Marks

The following terms are trademarks or service marks of the IBM Corporation in the United States or other countries:

IBM

ThinkPad

The following terms are trademarks of other companies as follows:

Microsoft	Microsoft Corporation

Windows	Microsoft Corporation

Windows NT	Microsoft Corporation