Hi
1)In my boat i have 3 years old 220Ah victron AGM house battery , now i am planning to increase capacity with one more 220Ah battery. Should i buy two new battery or i can just add one more new battery to old battery?
2) If i am going to buy new batteries , i am thinking to buy GEL 2x220Ah. Is it problem for Gel battery to be charge from normal engine alternator 55A,or i have to install some additional regulator?
Thank you
Hi Mikula,
sorry for the delay of th reply...hope you'll be interrested.
1) Never add or change battery from a battery bank without proper evaluation of the capacity and internal resistance of every single battery. I you have unballanced batteries in your bank, you'll lose the benefit of your brand new one.
The question you should ask yourself is ? Why should I increase the battery capacity ?
Is it because my consumption increases ?
or Is it because my energy storage decreases ? (charging system or battery failure)
Accordind the answer, the response won't be the same.
2) About charging needs, the best is to use a 4 steps charger device to respect the maximum battery bulk current, absorption and float voltages. for 2 x 220 Ah batteries, no problem with a 55 A bulk current (generaly bulk current must be lower than 20% capacity), but batteries and wiring should be balanced to have the same currents in every battery. As for absorption voltage, you need to check your alternator to respect the Gel Battery absorption voltage specs (maximum 14,5 V)
VRLA batteries does not support equalisation charge, because electrolyte must not "boil".
Keep in mind that heat is the worst battery enemy. Every 10°C above 20°C shortens the battery life by 2.
Regards.
Bruno.
