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Rectangular black lithium-ion laptop battery, 48WH 11.4V 4080mAh

KingSener

KingSener PA5278U-1BRS laptop battery 48WH 11.4V 4080mAh

SKU CH-JKB8-QM3S4 MPN PA5278U-1BRS

Replacement lithium-ion battery rated 48 Wh and 11.4 V for Toshiba Portégé X30 and Tecra X40 series laptops

  • Battery TypeLithium-Ion
  • Battery Voltage11.4V
  • Battery Capacity48WH/4080mAh
  • 48Wh capacity delivers extended runtime for compatible Toshiba laptops
  • 4V lithium-ion chemistry provides stable power output for daily use
  • 4080mAh rating supports prolonged mobile productivity sessions
  • Replaces PA5278U-1BRS and PA5278U part numbers for direct compatibility
  • Fits Portege X30 and Tecra X40 series models including X30-D-123 and X40-D-11F

Direct replacement battery

The KingSener PA5278U-1BRS is a new lithium-ion battery built for Toshiba Portégé X30 and Tecra X40 series laptops. It matches the original 11.4V 48WH specification and fits models such as the X30-D-123, X30-E-11D and X40-D-145 without modification. Buyers needing a different voltage or a higher capacity pack will need another part.

Cool operation under daily loads

The 4080mAh cell runs at the standard 11.4V and produces minimal heat during typical office work or web browsing. No active cooling is required and the pack adds no audible noise to the system. Users who expect fan-assisted thermal management should look at larger workstation batteries instead.

Steady output through a full workday

Under sustained load the lithium-ion chemistry maintains a stable voltage curve until the 48WH reserve is depleted. The pack is rated for hundreds of charge cycles and includes a two-year manufacturer warranty. Shoppers who need hot-swap capability or a secondary bay battery will find this single internal unit does not support those configurations.

Highlights

  • 48Wh capacity delivers extended runtime for compatible Toshiba laptops
  • 4V lithium-ion chemistry provides stable power output for daily use
  • 4080mAh rating supports prolonged mobile productivity sessions
  • Replaces PA5278U-1BRS and PA5278U part numbers for direct compatibility
  • Fits Portege X30 and Tecra X40 series models including X30-D-123 and X40-D-11F

Specifications

BrandLUSONBAY
ModelPA5278U-1BRS
Part NumberPA5278U-1BRS PA5278U
Battery TypeLithium-Ion
Battery Voltage11.4V
Battery Capacity48WH/4080mAh

Questions about this item

How do I install the PA5278U-1BRS battery in my Toshiba Portégé X30-D, and which step do people often skip?

Power off the laptop, remove the bottom screws, disconnect the old battery cable before lifting it out, then connect the new 11.4 V 48 WH pack and reassemble; the step most often missed is unplugging the old battery connector first.

What maintenance or replacement will the PA5278U-1BRS lithium-ion battery need over time?

The 4080 mAh Li-ion cells gradually lose capacity; expect to replace the pack once runtime drops below your needs, typically after several hundred charge cycles.

What is the first limit I will hit when running the PA5278U-1BRS continuously on a Toshiba Tecra X40-E?

The 48 watt-hour capacity sets the runtime ceiling; under sustained load the battery will deplete before any thermal or voltage limit is reached.

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