I’m amazed (and thankful) that you guys escaped without serious injury. I also want to add my thanks for sharing the situation.
As you mentioned, I too have long thought highly of both components (Opus and Samsung) involved in the incident. Talk about a serious reminder that nothing is infallible (or beyond reproach) when it comes to dealing with Lithium-Ion technology…
/my speculation from observations
Agreed, and good eye.
I’m strongly inclined to believe that the battery that exploded (and there was ‘nothing left of’) had to have been in bay 3. As judging by the pattern left by shrapnel, and knowing that the charging position of the battery is positive to the top, it is logical that it vented in an almost 360° pattern which radiated from the top of the battery (away from the side of the battery). The bottom being a single, solid ‘plate’ did similarly, but with marginally less force, thanks to its construction (which I can only assume directed the majority of the force to the top).
It’s interesting to note though, that there doesn’t seem to be much damage at all to the underside of where the battery is assumed to have been in bay 3.
The above is what leads me to believe that the battery was at fault, and shorted/exploded faster than what the charger could react to.
That last sentence though is what really throws me though. I strongly agree with @mrpipes that one would think (hope) that the monitoring circuitry would catch whatever ‘condition(s)’ were encountered BEFORE things escalate to a full on venting condition.
It also reminds me that I am curious about a couple of things.
What version of the Opus did you own? 1.x, 2.0, 2.1?
Did you ever test the batteries in the charger (regularly or otherwise)? Meaning, to not just charge them, but to get the overall condition (such as resistance, max capacity, etc)?
I’ve got some 25r5’s here that are approaching 3 years old (if not already that old), and while the max capacity has dropped off to an average of around 1800mah… I’m overdue to test them again for the resistance measurements.
Fortunately, I have replaced the majority of them (in daily use) with newer 30Q’s. (But OTOH, that only means increased reserve potential at hand to vent [God forbid]).
My line of thinking is…
I’m wondering if the internal resistance of the battery falls too far outside of spec (for the charger to ‘safely calculate’ or measure), then a window of ‘fail condition’ could open up…and you’d get what we see here?
/my speculation from observations OFF
Knowing full well that there’s really no way to know exactly what happened, in what order, I am still inclined to believe that the more info we can piece together, might help for future knowledge. (Better to have extra details, and not be useful [now], than to not have them, and learn they could have been important [down the road])
/random thoughts I haven’t had time to process yet
- how can a battery seemingly explode in place, leaving no remnants embedded in the charger (adjacent to the side of the battery, underneath the battery)?
- IF the battery started to vent (blowing both ends off of the charger where the battery was) from the ends first, was there then a further degradation of conditions which expelled the battery before it “exploded into nothingness”? (Which could explain there not being any shrapnel embedded in the ‘side wall’ of the chassis underneath the battery. But then proposes another question of “in order to eject the battery, one would think there would have to have been force exerted from the bottom side of the battery” [between the battery and charger] which again implies there should be shrapnel embedded in the area of bay 3)
So many questions… Such limited information out there (not pointing at you Dan, just touching on Li-ion venting conditions testing that’s in the public domain).
Times like this make me wish Mooch was able to run a series of venting tests in a controlled environment using a high speed camera (with varying chargers and batteries).
Sad day. But invaluable reminder.
Thank you again.