Did a small flight about 1.2km out , all of a sudden battery started dropping rapidly from 60% until it auto landed . It’s a flight iv completed  many times before with more than 50% remaining . To frighten to ever use this battery again

What does the DJI Go 4 battery stats say? and also look at the Warnings too

@Suren
Is there any way to test the cells in a battery

Hi, thanks for reaching DJI Forum. We do apologize if you have some issues with your aircraft. Kindly provide some screenshots for us to help you better. Also, I'd like to know when was the last firmware update you performed to your drone? We're here to help you. Thank you.

The Go 4 App will show you the battery voltages. You can see if a cell is different to the others. It may be worth running the battery as low as you can get it and let it cool and charge it again. Fly it in the aircraft until it will no longer fly, just a foot or so off the ground once the battery goes down. Cancel the battery warnings. I have an Inspire 1 and it will tell you when to do this with its batteries. Good luck, I hope it fixes it. Also check that it has not puffed. If it has I would not use it.

Please post your flight log to this link provided below and once done post that link back
http://www.phantomhelp.com/LogViewer/Upload/

I am sad for you / i had similar issue with my battery  before that my MA cannot fly though my battery fully charged
becaused  an error message  there  says insert your battery in proper position  / i contacted DJI support and they replaced it  .
So it seems some batteries software is defected