Caution Quality Problem

Having purchased this battery for my new Eos 70d in anticipation of a long journey, I am very disappointed. Indeed, I fully recharged there two weeks and the battery I tested so far everything is ok. After 2 weeks I put it back in the device that tells me that the battery is empty! I recharge fully again, insert it and then everything is ok. I turn back the next day the EOS70d that tells me that the battery is at 76%, without having used at all ... Unfortunately, I'm leaving tonight and I'll have run with original battery only ... Very disappointed, maybe the same problem as the user of the 6D?
edit the 06/11: not having been able to return since I left for 15 days and that I need 2 batteries, I confirm that this copy works well with the 70d. Unfortunately, I also confirm that it will discharge itself. The last straw for a spare battery as it loses 60% of capacity in three days kept in its box! So if you rely on it to take over, it is empty and useless. In short recharge every day against every 2 days for the original battery ...