How to replace the battery in a ThinkPad T431s in five simple steps. Estimated time required 5-10 minutes.
Step 1: Remove eight screws on the back (🔴) and remove the cover.
Step 2: Unplug the battery (🟠) and remove additional four screws (🔴).
Step 3: Take out the old battery and put in the new one.
Step 4: Screw the four battery screws back in (🔴) and connect the battery to the mainboard (🟠).
Step 5: Put the cover back on and screw the eight screws back in (🔴).
More detailed guide:
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