I thought it was something I was doing. I've been thru 3 batteries in 2 months. I ended up buying a dozen replacements from Amazon. I had trouble finding them locally.
I was on a redear trip with clients in May and in a shallow area. I went to turn slightly and when I hit the remote, it started the motor and turned like I wanted but wouldn't shut off. Luckily I was able to get the motor unplugged before we ran ashore. I changed the battery and it worked perfectly. The scary part is I had zero warning of a problem.
I think most of the issue with the batteries is the fact you and I both troll most of the time and are on the remote constantly. Granted, the remote on my Terrova 80 battery lasted over a year of constant use pulling cranks.