BYD Atto 3 12V starter battery failure

Have also installed a kings 12v 60ah battery into the car today. width is pretty much correct and the mount that you remove can somewhat fit if u reverse the bottom mount the other way and rescrew it back in with flatter screws. however I just basically ratchet strapped it down lol.

Only 2 things to make sure of
the + terminal on the byd has 2 lips that might prevent it from being seated flust with the bolt, dont overscrew it as it might crack the plastic. Will probably just add a washer underneath or a connection for a battery monitor underneath to make it a good flush fit.

the - terminal angle is fairly stiff at 90*, that needed a bit of work to screw on, but otherwise it works.

@jktiet, I also ratchet strapped the battery down. Hasnā€™t moved.

Just so you know, every 3 to 4 months, you will need to manually charge the battery using a common multi-stage battery charger to equalise the cells. The 13.8V from the vehicle is not high enough. I used an automatic 14.6V 8A charger and left it on until the charge cycle stopped and it went to float (it took about 3 hours).

I hadnā€™t done an external charge for at least 4 months, and I noticed the battery voltage suddenly dropped well below 13V for the first time. See the attached graph below from the Victron battery voltage monitor. Since the charge, it hasnā€™t dropped again.

Note, the timeframe shown on the graph below is over about 6 weeks.

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