I knocked my SK68 clone off my table and when I went to turn it on it was dead. It had a 14500 Trustfire cell in it and when I replaced it the torch was fine. Testing with a multimeter showed the cell voltage rising but when I put it on the charger (XTar WP2) the light flashed green/red/green/red/etc. I also tried charging with my accucel 6 but it didn’t like it either.
I’ve assumed the cell is bunk, but is it normal for lithium cells to die from being dropped or is it just because it’s a cheap nasty cell? If a single drop can kill a cell I will have to rethink the use of them in some situations.
I wouldn’t have thought so, but I’ve learned that what I learned is history, and quite often out of date so I ’oogled the question instead of giving an opinion. There’s often something new worth thinking about that changes my mind.
Your results will differ (Google gives you more of what you like in search results, which makes us easily fooled.
Supposedly there’s less of that if you have signed yourself out and deleted their cookies).
Safety Issues for Lithium-Ion Batteries - New Science - UL.com
Lithium-ion batteries … potential failure modes is still growing …… number of free falls to a hard surface. The cell sample is examined after a time following each drop.
from the latter:
“Another critical safety concern that our research identified is the thermal stability of active materials in aged batteries…. thermal runaway was triggered earlier in aged samples. In aged cells, separator melting and venting were delayed when compared with that of a fresh cell during the test. Data from a differential scanning calorimeter suggests that heat-generating reactions with the cells occur earlier for an aged cell….
The cell aged for 400 cycles shows a much more violent explosion than cells aged for less than 300 cycles.”
and there’s much else; just one more:
How to Service Cell Phone Batteries – Battery University batteryuniversity.com/…/how_to_service_cell_phone_…
Battery University
With the move to lithium-ion, fewer cell phone batteries fail during the warranty period … Some batteries get damaged due to dropping and other physical abuse. ….
The 'protection' circuits on those ____Fire cells are often not done very well. I've seen the positive end buttons so poorly welded that they could be pried off with just a fingernail.
Should it have been permanently damaged? One would hope not.
COULD it have been permanently damaged? Absolutely. Depends on the quality of the cell (Trustfire-may not be so good), how high the drop, onto what surface, onto what part of the battery….etc.
ANY cell, ANY, can be damaged by a drop onto a hard surface. Lithium presents more ‘interesting’ possibility’s for failure once damaged.
