I hired a crew and a crane to move the board upstairs to my workbench.
I added some fresh solder to the three battery terminals to prime them, then used my Hakko desoldering gun to suck it all back out. The battery pretty well fell off the board under its own weight.
I cleaned the area with alcohol and got some microscope shots. The worst is on the top negative end, but the traces seem intact even if exposed. I'll try to trace them and test continuity.
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