45N1070 45N1071. Lenovo ThinkPad X1 Carbon Series. Lenovo ThinkPad X1 Carbon (3444). Lenovo ThinkPad X1 Carbon (3448). Lenovo ThinkPad X1 Carbon (3460). Battery Type: Lithium-ion (Li-ion). 1.Li-Ion Laptop Battery 10.8V and 11.1V are in common use.
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