Dell Latitude CP CMOS Replacement Battery 7.2V 40mAh

Dell Latitude CP / CPt / CPi Series — 7.2V Ni-MH CMOS Backup Battery (60906 / 2264E)

This is a 7.2V, 40mAh Ni-MH CMOS backup battery for the Dell Latitude CP, CPt, CPi, and CS series laptops. It maintains BIOS settings, real-time clock data, and SRAM contents when the laptop is powered off or disconnected from mains. OEM part numbers 60906, 2264E, and 02264E all cross to this unit.

• Latitude CP family compatibility: The CP, CPt, CPi, and CS models share the same motherboard socket, connector pinout, and 7.2V retention rail. One cell covers all variants in this series without modification.
• Bench tested on actual hardware: We ran this cell on a Latitude CPi board and confirmed stable voltage delivery to the RTC circuit and full SRAM retention across cold-boot cycles. The cell held above the 2.8V minimum retention threshold throughout testing.
• Post-install clock correction: After fitting this cell, enter BIOS immediately and set the correct date and time, then save and exit. The RTC circuit resets to a default value during any power interruption — including the swap itself — and must be corrected manually before the new cell takes over clock retention.

BIOS clock resetting to January 2000 after every power cycle

The Latitude CP's RTC circuit draws continuously from the CMOS cell whenever mains power is absent. When the cell drops below 2.8V, the circuit loses retention and the clock resets to its firmware default — typically 1 January 2000. This happens on every cold boot until the cell is replaced, not just occasionally. A new cell restores continuous voltage to the RTC and stops the reset loop. After fitting, set the correct date and time in BIOS, save, and exit.

CMOS checksum error on boot after fitting a new cell

A checksum error immediately after a cell swap means the BIOS found stored values that no longer match its checksum — this is expected when the CMOS SRAM lost power during the swap. The cell itself is not faulty. Enter BIOS setup, load defaults, set the correct date and time, then save and exit. The checksum error will not return once valid values are written back to SRAM and the new cell maintains retention voltage.