I seen that a bunch of gold can pile up on the batteries, but I haven't had the knowledge nor courage to do it. Did you discharge the batteries first? Lithium I know tends to be more reactive than that.
To be more accurate, the gold isn't in the battery and you have it within the outer shell, however since i'm interested in lithium recovery in a safe way, i feel there is a lot more info you could provide and try to innovate learn and teach at same time.
