22 Year Battery Evolution RV -> RV & Home -> RV w/Solar & Home
For 17 years I used golf cart batteries and Honda 2000i with my travel trailer. I used the Honda generator for power outages at home in the winter. My wife and drove from St. Paul, MN to Fairbanks, AK in 2018 and boon docked some, less than I would have liked due to battery capacity hassle.
In 2019 I built a dumb Daly BMS 120A-12v LFP. It performed far better than twin 6v GC batteries in series. I added 2K sine wave inverter to the trailer and swapped the OEM microwave for a Panasonic inverter-based microwave. All was good and boon docking became easier. And I added a Battery EVO 120a-12v to augment capacity.
Covid stalled another trip to Alaska, blah, blah, blah.
Minnesota winter killed power for almost two days last winter. I had a small 600 watt sine wave inverter to run my furnace for a few minutes on LFP batteries until I got the generator plugged in.
Finally, the window opened to go to AK again this year. I added 600 watts of solar and controller to the trailer. I bought another Battery EVO 120a-12v and tested the pair – yes folks the batteries were not the same vintage but paralleled just fine and delivered 240a. The DIY Daly 120a-12v unit was not good (discussion below) so I left it behind.
The winter power loss made me think I should DIY power crate. I made the travel trailer have the solar stuff run to an Anderson connector so I can plug in whatever I have. I took the 2K Inverter mounted in a crate with my 12 LFP converter and wired it through a BT smart shunt. All the batteries plug into the crate via Anderson plugs, or individually into the trailer for simple transport. So, the batteries can plug into the trailer directly or through the power crate. It is all seamless via Anderson connectors.
I use the power crate in the trailer and in my home. I can easily move the batteries in and out of the house to trailer.
We didn’t make it to AK. Longer story, but we boon docked more than ever this summer and never ran the generator and used up to 160A one night but had full charge by 1:30PM the next day. The flat mounted panels delivered about 450 Watts on average sunny days. Power demand was more – CPAP, microwave, Starlink, etc. It all worked flawlessly.
If I hadn’t had all the stuff evolving over time, I probably would buy a recommended self-contained unit. But I have been enamored with batteries for over 65 years. You wouldn’t believe what I made out of zinc-carbon battery guts as a kid. As a child I counted my personal wealth in batteries and wire…
Will Prowse and I came out of the same battery mold many decades apart. Will’s latest video on charge maintenance for 12v LFP came at the right time. I had just removed and discharged to 60% my EVO pair. So, I charged them back up and disconnected them and turned them off. I will monitor them monthly. I’d rather have full charge available in the winter.
My DIY Daly 120a-12v met with problems because the Daly BMS could not be turned off – I think. I had the recommended cheap shunt display showing the voltage, but when I went to charge it, capacity was below 20A! I didn’t have time to take it apart. I figured it was a lost cause.
When I finally took it apart my cell tester showed one cell below 1.2V! The rest were fine. I put the low one on a charger at 3.6v 1 amp. It came back slowly – I didn’t push it. I top balanced all22 four cells to 3.65v and load tested it at about .4C. It delivered 120Amps!
I added a four-pole switch to the Daly BMS monitor leads, leaving the B- lead attached since there is no other wires to drain anything this turns off the battery. I also added a fused momentary contact switch between B+ and B- to jump start the battery after I turn the four-pole switch back on. So, the DIY battery is back in business. The four-pole switch runs the BMS monitor leads to a plug for and individual cell monitor I can plug in when the battery is in the off position. I will check the battery periodically to see if I have serious self-discharge in the ‘bad’ cell.
This brings 22 years saga up to date. I hope you enjoyed it.
For 17 years I used golf cart batteries and Honda 2000i with my travel trailer. I used the Honda generator for power outages at home in the winter. My wife and drove from St. Paul, MN to Fairbanks, AK in 2018 and boon docked some, less than I would have liked due to battery capacity hassle.
In 2019 I built a dumb Daly BMS 120A-12v LFP. It performed far better than twin 6v GC batteries in series. I added 2K sine wave inverter to the trailer and swapped the OEM microwave for a Panasonic inverter-based microwave. All was good and boon docking became easier. And I added a Battery EVO 120a-12v to augment capacity.
Covid stalled another trip to Alaska, blah, blah, blah.
Minnesota winter killed power for almost two days last winter. I had a small 600 watt sine wave inverter to run my furnace for a few minutes on LFP batteries until I got the generator plugged in.
Finally, the window opened to go to AK again this year. I added 600 watts of solar and controller to the trailer. I bought another Battery EVO 120a-12v and tested the pair – yes folks the batteries were not the same vintage but paralleled just fine and delivered 240a. The DIY Daly 120a-12v unit was not good (discussion below) so I left it behind.
The winter power loss made me think I should DIY power crate. I made the travel trailer have the solar stuff run to an Anderson connector so I can plug in whatever I have. I took the 2K Inverter mounted in a crate with my 12 LFP converter and wired it through a BT smart shunt. All the batteries plug into the crate via Anderson plugs, or individually into the trailer for simple transport. So, the batteries can plug into the trailer directly or through the power crate. It is all seamless via Anderson connectors.
I use the power crate in the trailer and in my home. I can easily move the batteries in and out of the house to trailer.
We didn’t make it to AK. Longer story, but we boon docked more than ever this summer and never ran the generator and used up to 160A one night but had full charge by 1:30PM the next day. The flat mounted panels delivered about 450 Watts on average sunny days. Power demand was more – CPAP, microwave, Starlink, etc. It all worked flawlessly.
If I hadn’t had all the stuff evolving over time, I probably would buy a recommended self-contained unit. But I have been enamored with batteries for over 65 years. You wouldn’t believe what I made out of zinc-carbon battery guts as a kid. As a child I counted my personal wealth in batteries and wire…
Will Prowse and I came out of the same battery mold many decades apart. Will’s latest video on charge maintenance for 12v LFP came at the right time. I had just removed and discharged to 60% my EVO pair. So, I charged them back up and disconnected them and turned them off. I will monitor them monthly. I’d rather have full charge available in the winter.
My DIY Daly 120a-12v met with problems because the Daly BMS could not be turned off – I think. I had the recommended cheap shunt display showing the voltage, but when I went to charge it, capacity was below 20A! I didn’t have time to take it apart. I figured it was a lost cause.
When I finally took it apart my cell tester showed one cell below 1.2V! The rest were fine. I put the low one on a charger at 3.6v 1 amp. It came back slowly – I didn’t push it. I top balanced all22 four cells to 3.65v and load tested it at about .4C. It delivered 120Amps!
I added a four-pole switch to the Daly BMS monitor leads, leaving the B- lead attached since there is no other wires to drain anything this turns off the battery. I also added a fused momentary contact switch between B+ and B- to jump start the battery after I turn the four-pole switch back on. So, the DIY battery is back in business. The four-pole switch runs the BMS monitor leads to a plug for and individual cell monitor I can plug in when the battery is in the off position. I will check the battery periodically to see if I have serious self-discharge in the ‘bad’ cell.
This brings 22 years saga up to date. I hope you enjoyed it.
