Restoring an Electric Drill With RC Battery

My electric drill battery flat, I look for replacement but not acceptable price, so I think my RC batteries may replace it, however the RC batteries were already flat too, it cannot play the RC, but it still can use the drill.

The RC batteries are 11.1V so can fit into 12V drill, I solder a RC male T-pin connector inside the drill battery contact metal, cut out two notches on the base to fit the battery pack, and mount a vero tape to hold the battery.

That's all for it, save water save power!