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  Lenovo ThinkPad T420s T420si Laptop Battery 66+

Lenovo ThinkPad T420s, T420si Laptop Battery 0A36287 42T4844 42T4845 66+

List Price: $149.99
Our Price: $89.90
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6 Cell Replacement Battery for Lenovo ThinkPad T420s, T420si 66+

This brand new Lenovo ThinkPad T420s, T420si replacement laptop battery features lithium-ion cells. Li-ion battery technology provides longer run times with less weight. In addition, Li-ion batteries are not subject to the memory effect common with older battery technology. This laptop battery replacement is 100% compatible with the original battery specifications and is individually tested and backed by a 2 Year warranty.

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  • Useful Life:
  • XTend replacement computer battery
  • 11.1 Volts - also compatible with 10.8 Volt systems
  • 3600 mAh 44Wh
  • 6 Cell Li-ion
  • Samsung (South Korea)
  • Black
  • Assembled in China
  • 2 Year Warranty
  • 30 day full satisfaction guarantee
  • 300-500 recharge cycles

THIS BATTERY ONLY WORKS WITH THE Lenovo T420s AND T420si. This battery will not work in the T430s or T430 models.

You can expect about 5 hours to 5-1/2 hours of run time with this computer battery when new, depending on your energy use. If you are looking for even longer battery run times, check out our extended run battery for your Lenovo laptop.

Replaces these many Lenovo ThinkPad laptop battery part numbers:


Laptop Battery Express only deals with brand new premium computer batteries. We never carry recycled or used batteries. We only use the highest quality cells inside the battery pack so you will have a long service life (300-500 recharge cycles). We do not use cheaper battery cells which can wear out in a little as 6 months. Our inventory turns rapidly and you will always receive a freshly manufactured battery.

Compatible AC Power Adapters designed for this product
AC adapter for Lenovo Laptops 20 Volts 4.5A 90 watts 7.7mm-5.5mm Pin Inside connector
Our Price: $49.00

AC adapter for Lenovo Laptops 20V-4.5A 90 watts 7.7mm-5.5mm Pin Inside connector

This battery & adapter are compatible with the following laptop models. If your battery or adapter part number is listed above, it will be compatible even if it is not listed below.

Lenovo Laptop Batteries > ThinkPad T420s
Lenovo Laptop Batteries > ThinkPad T420si 
IBM Laptop Batteries > ThinkPad T420s
IBM Laptop Batteries > ThinkPad T420si