journey on
New member
Well, 3 mos to the day, that lithium battery is in Journey On and operating as expected, a glorious milestone.
First of all, I'd like to thank Bob/thataway for sharing his battery configurations with me. Just knowing that someone else had done it was invaluable. I also read various discussions of battery chargers and batteries, both on the C-Brats and elsewhere. Thanks to all, and I make no claims to originality, but appreciate all the insight.
OK, here we go. The prices of LIFePO4 batteries had me ignore the idea of using them. Then I saw the youtube by Will Prowse on the 100 ah Chins battery, where he gave it a good review: cells, packaging and BMS.
So, again I thought it through. 1 ea li battery and 1 ea battery charger would save me 100 lbs in the stern of the boat, since I would replace 2 golf cart batteries. But I would have to save the Group 31 flooded lead acid to both serve as a charger buffer and a starting battery. I also reviewed the house loads which were driven by the refrig at 3.5 amps at 50% duty cycle (need that cold beer.) So say that it's 50 ah/day.and a 100 ah li battery could handle that and more.
Amazon delivered a Chin 100 ah li battery for $390 (w/tax,) and a Renogy 12V 20A DC to DC On-Board Battery Charger for $120. I picked the charger because it's output was less than half of the Honda output and the cheapest decent one. And I sat and looked at them and read the manuals, several time. Also please note this wasn't the last of the costs, which I didn't add up but were probably ~$250 more.
The first step was to remove the old golf cart batteries. I'm as old as Bob, so when Pete, my son, came down, I asked his to help remove them. He got them out of there by himself, God bless him again. The next step was time consuming, such as removing all the spare wires and re-routing what was left. Then I mounted the li battery and the charger. The battery went as far inboard as possible. It was light, 1/2 the weight of a single golf cart battery, 38#. The charger was mounted up-side-down to the bottom of the coaming step. Next was the rewiring: battery switch, battery, charger, lead from the motor, control switches. Those damn control switches had to be purchased, mounted at the helm and wired. They were for turning on the charger (normally the motor ignition does this,) and a 1/2 rate charge. I feel both are needed when you're plugged in to shore power. Judy installed the under cabinet tie wraps, bless her.
So, now everything is wired, I turn on the battery switch and the cabin lights give a draw of 0.7 amp (led's.) Try charging, nothing. Well, I'm not totally devastated, I'll check it tomorrow. And I did: one wire not connected. Fixed that, it all works: charges when the D+ switch is thrown, goes to 1/2 rate when the LC switch is thrown, cabin lights are on as are the chart plotters, etc.
Now on to clean up the boat. Yes it's a mess. And I'll post if this works or if it doesn't.
Anyone need 2 ea Trojan golf cart batteries? In SoCal.
Boris
First of all, I'd like to thank Bob/thataway for sharing his battery configurations with me. Just knowing that someone else had done it was invaluable. I also read various discussions of battery chargers and batteries, both on the C-Brats and elsewhere. Thanks to all, and I make no claims to originality, but appreciate all the insight.
OK, here we go. The prices of LIFePO4 batteries had me ignore the idea of using them. Then I saw the youtube by Will Prowse on the 100 ah Chins battery, where he gave it a good review: cells, packaging and BMS.
So, again I thought it through. 1 ea li battery and 1 ea battery charger would save me 100 lbs in the stern of the boat, since I would replace 2 golf cart batteries. But I would have to save the Group 31 flooded lead acid to both serve as a charger buffer and a starting battery. I also reviewed the house loads which were driven by the refrig at 3.5 amps at 50% duty cycle (need that cold beer.) So say that it's 50 ah/day.and a 100 ah li battery could handle that and more.
Amazon delivered a Chin 100 ah li battery for $390 (w/tax,) and a Renogy 12V 20A DC to DC On-Board Battery Charger for $120. I picked the charger because it's output was less than half of the Honda output and the cheapest decent one. And I sat and looked at them and read the manuals, several time. Also please note this wasn't the last of the costs, which I didn't add up but were probably ~$250 more.
The first step was to remove the old golf cart batteries. I'm as old as Bob, so when Pete, my son, came down, I asked his to help remove them. He got them out of there by himself, God bless him again. The next step was time consuming, such as removing all the spare wires and re-routing what was left. Then I mounted the li battery and the charger. The battery went as far inboard as possible. It was light, 1/2 the weight of a single golf cart battery, 38#. The charger was mounted up-side-down to the bottom of the coaming step. Next was the rewiring: battery switch, battery, charger, lead from the motor, control switches. Those damn control switches had to be purchased, mounted at the helm and wired. They were for turning on the charger (normally the motor ignition does this,) and a 1/2 rate charge. I feel both are needed when you're plugged in to shore power. Judy installed the under cabinet tie wraps, bless her.
So, now everything is wired, I turn on the battery switch and the cabin lights give a draw of 0.7 amp (led's.) Try charging, nothing. Well, I'm not totally devastated, I'll check it tomorrow. And I did: one wire not connected. Fixed that, it all works: charges when the D+ switch is thrown, goes to 1/2 rate when the LC switch is thrown, cabin lights are on as are the chart plotters, etc.
Now on to clean up the boat. Yes it's a mess. And I'll post if this works or if it doesn't.
Anyone need 2 ea Trojan golf cart batteries? In SoCal.
Boris
