Bill@Moxie
New Member
Hi,
We're planning on installing Solar and Lithium Ion batteries on our sailboat. We have a 12 volt DC system on the boat. We've measured our battery compartment and we can hold 4 Group G sized batteries with some room left over. We are looking at installing 3 100 Amp hour LiFePO4 batteries in parallel for a 300 Amp Hour 12 volt bank, and a 12 volt AGM lead acid starting battery.
We have the following charging sources:
We are considering the Renogy DCC50S DC to DC 50 Amp with MPPT charger. We've read that one of the shortcomings of this unit is the low maximum solar input voltage, but we only have two panels and will be wiring them in parallel due to some shading issues at the dock.
A concern that we do have with the Renegy DCC50S that we have ready in the forums here is that if the house bank is Lithium, the charger will not trickle charge the starter battery. Is this correct? We do carry a portable lithium jumper battery, but one thought we had is to use a 1/2/combine switch for the batteries to allow us to briefly switch to "combine" to allow us to jump the engine from the house bank. The M25 diesel engine is starting current draw is well below the combined 300 Amps the lithium house bank would be able to put out. Is this an ok option?
We have read that that maximum input to the Renegy batteries is 50 amps. Can I assume that since we'll have 3 in parallel that the input is 150 amps? It seems that due to the fact a battery could fail, or they may reach a cut off point we should limit the charging input to the single battery maximum of 50 Amps. On our drawing we have added a switch to allow us to switch from the DCC50S to a Victron AC to DC charger in order to stay beneath this limit. Is this necessary?
I've attached a picture of what we are thinking. We've tried to work out what fuses/circuit breakers we'd need to protect the system and ourselves and are not quite sure we have it right.
Thanks!
Bill
We're planning on installing Solar and Lithium Ion batteries on our sailboat. We have a 12 volt DC system on the boat. We've measured our battery compartment and we can hold 4 Group G sized batteries with some room left over. We are looking at installing 3 100 Amp hour LiFePO4 batteries in parallel for a 300 Amp Hour 12 volt bank, and a 12 volt AGM lead acid starting battery.
We have the following charging sources:
- 2 x 110 Watt Solar Panels (220 watts total, we had bought these a couple years ago and never installed them)
- 55 Amp Alternator on a 21 HP Diesel Engine
- Shore Power
We are considering the Renogy DCC50S DC to DC 50 Amp with MPPT charger. We've read that one of the shortcomings of this unit is the low maximum solar input voltage, but we only have two panels and will be wiring them in parallel due to some shading issues at the dock.
A concern that we do have with the Renegy DCC50S that we have ready in the forums here is that if the house bank is Lithium, the charger will not trickle charge the starter battery. Is this correct? We do carry a portable lithium jumper battery, but one thought we had is to use a 1/2/combine switch for the batteries to allow us to briefly switch to "combine" to allow us to jump the engine from the house bank. The M25 diesel engine is starting current draw is well below the combined 300 Amps the lithium house bank would be able to put out. Is this an ok option?
We have read that that maximum input to the Renegy batteries is 50 amps. Can I assume that since we'll have 3 in parallel that the input is 150 amps? It seems that due to the fact a battery could fail, or they may reach a cut off point we should limit the charging input to the single battery maximum of 50 Amps. On our drawing we have added a switch to allow us to switch from the DCC50S to a Victron AC to DC charger in order to stay beneath this limit. Is this necessary?
I've attached a picture of what we are thinking. We've tried to work out what fuses/circuit breakers we'd need to protect the system and ourselves and are not quite sure we have it right.
Thanks!
Bill
