Pry it out, any way you can without damaging the tool. Damage the battery, not the tool if you have to. Spray it down with vinegar first, that might help loosen it up. When you have it out, clean up the area with vinegar on a cotton swab first, then clean the contacts with a fine sandpaper or emery board. Careful with the vinegar, don't let it go where you don't want it.
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Pry it out, any way you can without damaging the tool. Damage the battery, not the tool if you have to. Spray it down with vinegar first, that might help loosen it up. When you have it out, clean up the area with vinegar on a cotton swab first, then clean the contacts with a fine sandpaper or emery board. Careful with the vinegar, don't let it go where you don't want it.