battery protection

That is the function of the charge controller, to keep that from happening. As far as I know there is no such product other than that but, I think it could be made. A redundant voltage sensor could be wired to hold in a contactor and if too high a voltage is reached, cause the contactor to drop out. It would have to be reset manually.

Kind of like the overloads on a motor starter only they work by excessive heat from over amperage.
 
This would have to work by overvoltage. The only problem would be at sunrise, something would have to pull in the contactor. If that part of it was automated and there was an over voltage "trip" the battery voltage would drop off quickly and then it would pull in the contactor, overvoltage, trip and drop out again and again.

This is sort of how a simple on/off charge controllers like the Trace C-30-A works, only you can set the low voltage reconnect and high voltage disconnect where you want them. But as far as I know they do not have over voltage protection.

 There would have to be a relay to open the "sunrise" circuit once it pulls in the contactor and close the "seal in" circuit to start charging but allow it to drop out in a high voltage fault and be manually reset.

Again this would work like 2 and 3 on a motor starter. 3 is the start and 2 is the seal in but the overloads protect by opening X2 and have to be manually reset. But, the coil would use power... Hmmm.
 
Uhh, sorry about that. I was just thinking out loud.
How about sharing with us the name brand and model of that charge controller that failed, so I know not to ever buy one?