Rebuild Bosch cordless drill batteries?

I have been leaning towards Primecell.

Yes. Makes sense, and I learned about this probably 30 years ago, from battery handbooks from the manufacturers. Actually, they recommended putting a diode around each cell, to prevent damage from forward charging. Diodes were expensive then, so few people did this, but it may now make sense.

Joe Gwinn

I let X (name sounds like "Interstate Battery") rebuild my Ryobi 14.4v nicad battery and it was as gutless as the original, then it died (lost all charge after a day or two, full charge good only for a couple minutes) less than a year later. Most places upgrade the mAh rating but I think IB used the same or lesser capacity cells. I wasn't thrilled.

But how do you determine the effectiveness of the used protection circuitry in rebuilt UPSes? I put a new battery ($17, 7Ah LA) in my old UPS and about 5 years later, the test switch died. I figured it was time for a whole new UPS at that point. AFAIK, there is no way to test for damaged or almost-used-up MOVs, etc.

-- Happiness is not a station you arrive at, but a manner of traveling. -- Margaret Lee Runbeck

Then plug a surge protector into the outlet feeding the UPS. Or learn to solder and spend a couple dollars for new MOV or Transorbs.