Beisite L19C3P71 L19M3P72 L19M3P73 laptop battery 48.2Wh 11.58V for ThinkPad X1 Nano Gen 1

Replacement Battery for ThinkPad X1 Nano Gen 1

This 48.2Wh lithium-ion cell replaces part numbers L19C3P71, L19M3P72 and L19M3P73 for the ThinkPad X1 Nano Gen 1st Series. It delivers 11.58V and matches the original 3ICP5/74/78 form factor in black. Supplied new with a 12-month warranty, it restores mobile power for owners of the 20UN chassis. Buyers needing a higher-capacity pack or a different voltage platform cannot use this unit.

Drop-In Fit for the Ultra-Light Chassis

The battery slots into the existing compartment without adapter cables or firmware updates, freeing the user from a tethered power brick. It connects directly to the system board using the factory connector layout, so no soldering or bracket modification is required. Installers should verify the 20UN model suffix before fitting. Builders working on any other laptop line or a second-generation Nano will find the mechanical keying incompatible.

Steady Output Through a Full Work Day

The 48.2Wh rating sustains typical office workloads across multiple hours on a single charge, avoiding the sharp voltage drop seen in aged cells. Lithium-ion chemistry maintains stable 11.58V delivery until the low-capacity warning triggers, so performance does not throttle mid-task. The pack is not designed for rapid-charge cycles beyond the OEM controller limits, and it cannot support external power-bank pass-through.