Systems with Simplo batteries left with just minutes of battery life.
Microsoft says that it is going to release a software update for Surface Pro 3 systems that should restore their battery life without requiring any hardware fixes.

Over the last few months, there have been scattered claims that some Surface Pro 3 systems are suffering from extremely poor battery life. Some amount of battery degradation over the lifetime of a system is to be expected, but some owners of Microsoft's tablet computer are saying that battery life has dropped to as little as one to two minutes, which is far below what it ought to be, even after many charging cycles.

Windows' own battery health reporting shows that the charge capacity of affected batteries has dropped precipitously, from the 42Wh they started with to, in some cases, less than 0.2Wh.

The common element appears to be the battery manufacturer. Surface Pro 3 batteries are supplied by two companies: LG and Simplo. While LG systems appear to be fine, some Simplo systems are suffering a substantial drop in battery capacity, and accordingly, a drop in battery life. The fix will presumably correct the issue and restore the capacity to what it should be. There is no word yet on when the fix will be delivered, however.

The update may come too late for some Surface Pro 3 users, though. Some report that Microsoft support has demanded payment for investigating the issue and has offered replacement systems, bought for a fee, to resolve it. Microsoft says that this is not the correct policy and that even out-of-warranty systems that are suffering from the issue should be supported at no cost.