Somewhat to my surprise, the eBay vendor responsible for those curves sent three replacement NP-FS11 batteries, commenting:
We’ve sent all your comments to the factory and ask them for a total quality inspection in this batch of batteries.
Here are the capacity curves for an initial charge, a test, recharge, and another test on each pack. The curves match up reasonably well (the top & bottom traces are nearly exact overlays), so I believe the results are accurate.
One pack is the best I’ve seen yet. The other two are junk, pure and simple.
So, to summarize:
- One of three batteries DOA in first batch, others weak
- Two of three batteries DOA in replacement
Overall, that’s a 50% failure rate even if you have relaxed standards…
I decided that, despite their “customer service”, this level of quality deserves the dreaded Negative Feedback checkbox.
If I had any confidence that spending more on the batteries would get a higher quality product, I’d do it. The question is, would another order of magnitude make any difference?