You get what you pay for -- and no more.
Remember that Free Shipping means that the cost of packing and posting an item is included in the selling price. Which makes the actual value of the item even lower.
You could in theory get your money back by returning the batteries to China with tracking, but this is going to cost you $40 or more. So, leave appropriate feedback.
Remember that you will be judged on your feedback as much as the seller. Calm and factual is the way to go. Which, btw, also means not ALL CAPS, which is considered to be shouting and very rude.
"Poor quality dont hold charge over 1 hour " might be appropriate.
At the same time you will be asked to leave Detailed Seller Ratings. These are much more important than feedback. A normal transaction gets 5 stars. The lowest rating is ONE STAR. No stars is a free pass.
If a seller's DSRs drop to 4.3, his fees may rise, his ability to list and sell on eBay may be restricted, the value and number of items he can sell may be restricted, or his customers' payments may be held for up to 21 days. Or he could have his membership ended.
You might also try asking the credit card you really paid with for a chargeback. Some cc's do not require proof of delivery only proof of shipping.
