This is what happens when you invest in cheap lipos .This is a friend of mine's buggy in the usa batterys used turnigy 14.8v 4s 5000mah .

He posted the photo on facebook with a little story .Alot of customers say why should i pay more for another more expensive pack when i can buy 3 cheap packs ok fair enough but do your math example price/how many charge cycles/runtime/performance and warranty and you will quickly find out why its better to spend a little more for decent a pack .