Charging Lifepo4 with shorepower

[HRTKD]

I have 6 gauge between the batteries and the rv power center (charge/converter). I know when I install my stand alone charger I will install 4gauge between the charger and the batteries.

I use 6 gauge between my 55 amp converter and the LiFePO4 battery bank. Works great! But it depends on how long the cable is. Mine is less than 4' round trip. .75% voltage drop with those wires/amps/volts.

 

[Jbarnes1719]

I use 6 gauge between my 55 amp converter and the LiFePO4 battery bank. Works great! But it depends on how long the cable is. Mine is less than 4' round trip. .75% voltage drop with those wires/amps/volts.

Yeah mine is between 18-20 ft.

 

[Jbarnes1719]

Yeah mine is between 18-20 ft.

I have a 5ver and the always put the batteries in the front and the power center in the middle or back area.

 

[HRTKD]

Yeah mine is between 18-20 ft.

Yep. 6 gauge isn't going to cut it. Neither is 4 gauge. According to the calculator I use, 4 gauge will allow a 4.69% voltage drop.

Amps: 55
Distance: 40 ft (you have to account for the round trip, not just the one-way distance)
Volts: 12

Interactive Wire Size Calculator

Battery Chargers, Inverters, Solar Components, and Wiring Supplies for Boats, RVs, and Off-Grid Applications.

baymarinesupply.com

 

[Jbarnes1719]

Yep. 6 gauge isn't going to cut it. Neither is 4 gauge. According to the calculator I use, 4 gauge will allow a 4.69% voltage drop.

Amps: 55
Distance: 40 ft (you have to account for the round trip, not just the one-way distance)
Volts: 12

Interactive Wire Size Calculator

Battery Chargers, Inverters, Solar Components, and Wiring Supplies for Boats, RVs, and Off-Grid Applications.

baymarinesupply.com

Not sure I follow. When we are on shorepower the converter will be running the rv. When we are not power from the batteries will feed 20 feet to the power center for a 25 amp max load. Most of the only 15 amps at intervals. The battery charging wire will only be 6 foot max from the charger the batteries.

 

[time2roll]

Even at 5% that 14.4 converter will put 13.5 volts on the battery. If plugged in I would not stress too much on that because time is on your side. Now if trying to minimize generator time consider a second charger near the battery with short fat wire.

 

[Flux]

I have thought of using a dc-dc charger. Another poster suggested a stand alone charger that could be plugged in anytime you have access to shore power or use my Yamaha gennie. Charge times are fairly quick on lifepo4. I believe that is the way I am going. I also have currently a 200 watt solar setup that will eventually be 600-800 watts. I have 6 gauge wire but I probably rewire to 2-4 gauge to be safe. My draws are not that great. Just want to be able run everything but the air.

I am becoming a fan of the victron stuff. The IP65 charger I got has a ton of settings, it's nice and connects right up to the phone via bluetooth and I could see how many AH my old AGM took. I am expecting good things from the Orion 12-12 and others who have it really like it. If you go all victron everything can connect in one app. But get the best equipment to do the job. Funny thing is that before Lithium took off there were very very few smart chargers to deal with AGM and other Lead Acid batteries charging from the alternator. I am tearing out some older stuff and replacing it with newer, better, more flexible, and cheaper equipment. LOL. I think my less than optimal charging equipment killed my very expensive AGM battery. There was also no way to know how much it really charged either, but all that changes now with the smart setups and Lithium.

 

[HRTKD]

Not sure I follow. When we are on shorepower the converter will be running the rv. When we are not power from the batteries will feed 20 feet to the power center for a 25 amp max load. Most of the only 15 amps at intervals. The battery charging wire will only be 6 foot max from the charger the batteries.

You made it sound like your converter/charger/whatever is 20' from the battery bank.

 

[Jbarnes1719]

Even at 5% that 14.4 converter will put 13.5 volts on the battery. If plugged in I would not stress too much on that because time is on your side. Now if trying to minimize generator time consider a second charger near the battery with short fat wire.

I’ll will just turn off the batteries at the disconnect when I am on shore power. When I am not on shore power I will use the batteries. The stand alone ac to dc charger will be within 6 feet of the batteries. Looking at big watt car stereo amplifier power wire to go from the charger to the batteries. It is fine strand with thousands of strands. Since current like to dance on the outside diameter of wire I figured this would work well.

 

[Jbarnes1719]

You made it sound like your converter/charger/whatever is 20' from the battery bank.

It is about 20 feet but my DC only load from the batteries to my power center is 25amps max with 30 amp fuses with everything running but the air conditioner. I will probably never be pulling all of that at once. My ac to dc charger for the batteries will be within 6 feet of the batteries. I may still replace the long run of wire anyway. My needs are to be able to draw from batteries longer than I can with my lead acid chemistry. I don’t have big loads to pull I just want to do it longer with damaging my batteries. All my lights are led. They use a total of 125 watts with them all on at once. The furnace fan motor is the biggest load at 11amps. I will probaby put a inverter in to run certain ac items but I will wire it appropriately and it will be mounted very near the batteries.

 

[Jbarnes1719]

I am becoming a fan of the victron stuff. The IP65 charger I got has a ton of settings, it's nice and connects right up to the phone via bluetooth and I could see how many AH my old AGM took. I am expecting good things from the Orion 12-12 and others who have it really like it. If you go all victron everything can connect in one app. But get the best equipment to do the job. Funny thing is that before Lithium took off there were very very few smart chargers to deal with AGM and other Lead Acid batteries charging from the alternator. I am tearing out some older stuff and replacing it with newer, better, more flexible, and cheaper equipment. LOL. I think my less than optimal charging equipment killed my very expensive AGM battery. There was also no way to know how much it really charged either, but all that changes now with the smart setups and Lithium.

I am actually going to disconnect the wire coming from my alternator after seeing some post about lifepo4 batteries drawing way more than the small 12gauge wire I saw on my 7 pin connector in the bed of the truck or some alternators can handle. Mine is 220amp but the wire is pitiful. I’ll just turn on the batteries for the safety brake. I’ll make sure my batteries are fully charged before I leave and my will solar help keep them topped off.