[OT?] Possible fix for defective 40v Black&Decker weed eater battery?

[L_D_Allan]

The 40x Lithium battery for the Black & Decker weed-eater showed up defective. I'm hoping there is something I can try to get it to work ok.

• Original: Lithium-Ion Type 2 54 Wh LBXR36 ... White, black, and orange
• Charger shows continuous fast red blinks, indicating "Defective"
• The "State of Charge" indicator has 0 of 4 lights, indicating "Flat"
• Black & Decker was ok about shipping a replacement battery.
• Didn't have to return the original battery, so I still have it.
• Replacement: Type 4 1.5AH 54 Wh Black, and orange
• Replacement battery works fine with charger.
• This appears to be similar to the replacement battery (except 2AH instead of 1.5AH):
  http://www.hardwarestore.com/battery-lithium-ion-2ah-40v-699877.aspx
  (The original battery was white, black, and orange)

It would be nice to wrestle with the original battery and get it working. A backup would be good to have.

Any suggestions appreciated.

 

[NoNotAgain]

Pull it apart and measure the voltage of the single cells. Any cell that measures low is junk.

54 watt hr isn't much of a battery with 40 volts.

My Milwaukee 18 volt lithium batteries are 4 amp, 72 watt hr.

 

[L_D_Allan]

Stale thread .... sorry (and also thanks for the reply which I was rude not to reply, and also didn't comprehend)

Since the OP, I've gotten more experience with LI-ION batteries and may understand the reply better.

My impression is that the weed-eater battery has multiple standard cells, such as 16850's. It might be worth trying to non-destructively disassemble the battery, and then check each cell. If any were defective/'dead, then consider replacing that cell.

Or am I still "unclear on the concept"?

It would be nice to have a backup weed-eater battery. It tends to take more than one charge to do my yard trimming.

 

[WalkIntoTheLight]

No, I think NoNotAgain meant that you could harvest the 18650 cells inside the battery pack, and use those cells for flashlights. Don't try to replace cells inside your battery pack. First, you're going to destroy the pack taking it apart (they're designed not to be taken apart). Second, you don't want to mismatch cells inside a battery pack. Third, the pack is designed to use the cells that it uses, and substitute brands are not necessarily safe.