This is the problem with lead acid battery technology. The acceptance rate tapers dramatically as you get above 70 or 80 percent state of charge. On boats where batteries are the only power, you run them down to 50 percent and charge to 80 percent. That is the sweet spot. The problem is that with AGMs you need to charge to 100 percent periodically (perhaps once a week) or they will die young.
This is also why all the hype about LiFePo4 batteries. They will take a very high rate of charge right to the top. You do pay a price for the capability.
