Lenovo 5B11B79218 Internal Battery 4-Cell 90Wh Li-Ion for ThinkPad P1 / X1 Extreme

The Lenovo 5B11B79218 is a genuine internal battery engineered for high-performance ThinkPad P1 and X1 Extreme workstations. With a 90Wh capacity and 4-cell lithium-ion design, it delivers extended runtime for demanding tasks like 3D rendering, video editing, and software development. Unlike generic replacements, this battery is built to Lenovo's exact specifications, ensuring seamless integration and reliable power delivery.

Highlights

• 90Wh capacity for long work sessions away from an outlet
• 4-cell lithium-ion chemistry for stable voltage and durability
• Designed for ThinkPad P1 Gen 4-6 and X1 Extreme Gen 4-6
• Internal installation for a clean, integrated look

In daily use

This battery restores your laptop's mobility, letting you work through meetings, flights, or field work without constantly hunting for power. Its 15.36V nominal voltage matches the original design, so your system reads charge levels accurately and charges efficiently. The black casing blends invisibly inside the chassis, and the built-in protection circuits guard against overcharge, over-discharge, and short circuits for long-term reliability.

Full specifications

• Battery technology: Lithium-Ion (Li-Ion)
• Capacity: 90 Wh
• Number of cells: 4
• Voltage: 15.36 V
• Ampere-hour capacity: 5.86 Ah (5859 mAh)
• Product type: Internal laptop battery
• Compatibility: Lenovo ThinkPad P1 Gen 4, X1 Extreme Gen 4, P1 Gen 5, X1 Extreme Gen 5, P1 Gen 6, X1 Extreme Gen 6
• Colour: Black
• Rechargeable: Yes
• Safety features: Overcharge protection, over-discharge protection, short-circuit protection

Final note

Restore your ThinkPad's endurance with a battery that matches the original in every critical spec.