We have had some "battery communication error" in flight for some time now and inspected our batteries carefully. Turns out most of our kits have their plastic frame melted near the connectors, see attached pictures. I'm pretty sure this is what causes battery capacity to suddently drop during flights and that's pretty creepy. Some of those kit are pretty old (150+ cycles) but others are kind of new (20-30 cycles). We have been told that DJI guarantees these batteries for 200 cycles. Also not all batteries of the same kit are melted this way.
Hypotheses:
1 - Poles get so hot during discharge that it melts the frame (would be an insanely bad design flaw by DJI but would not be the first one). Some of our batteries reach 65-70C degrees in discharge during summer. Still does not seem hot enough to melt plastic.
2 - Drone connectors are dirty and generate more heat during discharge.
3 - Charger poles are dirty and generate more heat during charging.

This is not an isolated incident, about 30% of our tb47/48 kits (we have 20 kits, 120 batteries) are like this. We also have some batteries stop providing power (shutting down temporarly) during flight when they reach about 70 degrees Celsius but I have been told by DJI that this was "normal" in order to protect the battery. Nice to see they want to protect batteries and not our $25k payload.

Any help would be greatly appreciated.

Hi podos, I'm so sorry to hear about the issue with your batteries. For fly safety considerations, it is not recommended to use the batteries again if it suddently drops during flights. Please contact our support team by sending an email to support@dji.com, provide us with the serial numbers of your batteries, if the batteries still within the warranty period, our team will help to open a case and you are able to send it in for service.

After sending the email, you'll get a request number, please let me know your request number, I'd like to help you keep an eye on it. Thanks.