Ask PYS: Power

Mixing Battery Types – George, on Jun 12, 2015 asked:

Hi Jeff, you upgraded my electronics on board my Hunter 50 cc. Now three years later I am in Asia, along the Thailand Malay border. My question is I have all AGM batteries on board with smart battery management on board. My starter battery is not holding charge and I need to replace it. They have no AGM batteries here in Langkawi. How serious is it if I get a non-AGM starter battery and what can go wrong? There is an ACR between house and start.

Hi George, it is nice to hear from you. Not great to mix battery types. But it’s a manageable situation; worst case will be the starter battery will slowly overcharge. If possible, get a flooded starter lead acid battery that has vent caps so that you can top-off the electrolyte as it boils quicker than usual.