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Old 07-25-2011, 11:05 AM   #10 (permalink)
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Location: 1000 Islands, Ontario, Canada
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It's ~130 bucks to replace the entire pack assembly, the store says.

I've already disassembled the pack, and will probably just swap out the single dead battery with a new one ***. Here's what it looks like:

The spade connectors on the wiring were soldered to the battery tabs.

*** I realize adding a new battery with full capacity to the older one creates an unbalanced pack, which could lead to the quick demise of the remaining original battery. (As the pack is discharged, the old battery will drain faster.)

The workaround is to monitor the battery voltage of the older battery, and ensure it's not drawn below the magic number of 10.5 volts under load. Below that voltage (1.75v per cell), a lead acid battery can be quickly, irreversably damaged.
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