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Install the CMOS battery

Follow instructions in this section to install the CMOS battery.

About this task

The following tips describe information that you must consider when installing the CMOS battery.
  • Lenovo has designed this product with your safety in mind. The lithium CMOS battery must be handled correctly to avoid possible danger. If you replace the CMOS battery, you must adhere to local ordinances or regulations for battery disposal.
  • If you replace the original lithium battery with a heavy-metal battery or a battery with heavy-metal components, be aware of the following environmental consideration. Batteries and accumulators that contain heavy metals must not be disposed of with normal domestic waste. They will be taken back free of charge by the manufacturer, distributor, or representative, to be recycled or disposed of in a proper manner.
  • To order replacement batteries, call your support center or business partner. For Lenovo support telephone numbers, see Support Phone List for your region support details.

After you install the CMOS battery, you must reconfigure the server and reset the system date and time.

When replacing the lithium battery, use only Lenovo specified part number or an equivalent type of battery recommended by the manufacturer. If your system has a module containing a lithium battery, replace it only with the same module type made by the same manufacturer. The battery contains lithium and can explode if not properly used, handled, or disposed of.

Do not:
  • Throw or immerse into water
  • Heat to more than 100°C (212°F)
  • Repair or disassemble

Dispose of the battery as required by local ordinances or regulations.

disconnect all power
The power-control button on the device and the power switch on the power supply do not turn off the electrical current supplied to the device. The device also might have more than one power cord. To remove all electrical current from the device, ensure that all power cords are disconnected from the power source.


  1. Touch the static-protective package that contains the new part to any unpainted surface on the outside of the server. Then, take the new part out of the package and place it on a static-protective surface.
  2. Install the CMOS battery.
    Before you install the battery into the socket, make sure that the positive side faces upward.
    Figure 1. Installing the CMOS battery
    CMOS battery installation
    1. Tilt the battery and insert it to the positive end on the socket. Make sure that the battery goes tight to the metal clip.
    2. Press the battery down until it clicks into the socket.

After you finish

  1. Complete the parts replacement. See Complete the parts replacement.

  2. Use the Setup utility to set the date, time, and any passwords.

Demo video

Watch the procedure on YouTube