There are three possibilities: (a) Your electrical system is being short-circuited, (b) your electrical contacts are defective, or (c) you're the one in million who just happened to get four batteries in a row that have manufacturing defects.
The fact that one of them discharged in 15 minutes has me puzzled. For a battery to discharge that quickly without some telltale signs of electrical shorting (smoking, sparking, excessive heat etc.) suggests that the problem is not a short circuit. I would check out all the electrical contacts if only to rule out possibility (b).
As for the one in a million chance, it's actually not quite that unlikely to happen if all those batteries were made in the same factory with the same lot number which is entirely possible.
Answers & Comments
There are three possibilities:
(a) Your electrical system is being short-circuited,
(b) your electrical contacts are defective, or
(c) you're the one in million who just happened to get four batteries in a row that have manufacturing defects.
The fact that one of them discharged in 15 minutes has me puzzled. For a battery to discharge that quickly without some telltale signs of electrical shorting (smoking, sparking, excessive heat etc.) suggests that the problem is not a short circuit. I would check out all the electrical contacts if only to rule out possibility (b).
As for the one in a million chance, it's actually not quite that unlikely to happen if all those batteries were made in the same factory with the same lot number which is entirely possible.
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