New to Lithium

[NeedToRetire]

I just purchased a new Fifth wheel that came standard with a 220 watt solar system. I had on hand two new 100AH Lithium LifePO4 batteries, I intended on installing them in our former TT, but trade it in on the new 5er. I had the dealer install the two 100AH’s instead of the Lead Acid.

We immediately took the new 5er on a three-week trip to warmer places and now back home I have some questions.

1: I today ordered a third 100AH battery to add capacity. At what state should I have all three batteries before connecting them all together? Is it just having them all at the same voltage? As a side note, all three will be the identical batteries and within 3-4 months of age.

2: When the campers not in use in the summer months, should I disconnect the solar? Also, what voltage should the batteries be at before doing so?

3: I am thinking about adding a inverter, just to run light loads like CPAP and TV. The Keystone camper I bought said “Inverter Ready” with some outlets marked inverter. With the current 220W of Solar and 300AH battery capacity, what size inverter would be recommended? I know it’s a bigger load, but with my current described configuration, could I occasionally run the Microwave with the right inverter & 300AH batteries?

4: I was hoping the roof was ready for another 220W panel, but it is not If our intentions are to ocasionaly be off grid 2-4 days, do I just need to bite the bullet and add it now. I'm not in love with monkeying with a brand new warranted roof though. On this 3 week trip, with our current configuration, we went 3-4 days unhooked/dry with no problem.

[Tony Ramirez]

1) I would have the ALL 100% SOC(remember, it's better to look at State of Charge than voltage w Lithiums), then hook them together.

2)If you aren't going to use it at all, then disconnect them, @ about 60%. I leave mine on w my fridge going when it's stored on the side of my house, no problems w solar.

3) My 2000W inverter runs my 1500W micro/convection no problem.

4) Just remember, it was almost Spring on this trip. If your plans are for mostly Winter camping, the low angle of the Sun will give you a lot less solar. If you were fine this trip w your setup, in Dec you might need more solar. Or run your gen or shore more.

[SteveJ.]

Originally Posted by NeedToRetire

I just purchased a new Fifth wheel that came standard with a 220 watt solar system. I had on hand two new 100AH Lithium LifePO4 batteries, I intended on installing them in our former TT, but trade it in on the new 5er. I had the dealer install the two 100AH’s instead of the Lead Acid.

We immediately took the new 5er on a three-week trip to warmer places and now back home I have some questions.

1: I today ordered a third 100AH battery to add capacity. At what state should I have all three batteries before connecting them all together? Is it just having them all at the same voltage? As a side note, all three will be the identical batteries and within 3-4 months of age.

2: When the campers not in use in the summer months, should I disconnect the solar? Also, what voltage should the batteries be at before doing so?

3: I am thinking about adding a inverter, just to run light loads like CPAP and TV. The Keystone camper I bought said “Inverter Ready” with some outlets marked inverter. With the current 220W of Solar and 300AH battery capacity, what size inverter would be recommended? I know it’s a bigger load, but with my current described configuration, could I occasionally run the Microwave with the right inverter & 300AH batteries?

4: I was hoping the roof was ready for another 220W panel, but it is not If our intentions are to ocasionaly be off grid 2-4 days, do I just need to bite the bullet and add it now. I'm not in love with monkeying with a brand new warranted roof though. On this 3 week trip, with our current configuration, we went 3-4 days unhooked/dry with no problem.

1] Charge each battery separately to 100% would be best, most safe.

2] For long term storage it is best to not keep the batteries full. 30-70% will work.

3] Check your documentation for allowable inverter capacity and specification requirements. A 2000 watt inverter and your 300 AH should run the microwave, assuming proper wiring.

4] You could always setup a portable solar setup. This would also give you the option to not park in the sunny areas in hat weather.

If you do not have one, get yourself a shunt battery monitor. Dry/dispersed camping is so much easier if so equipped. It's like a gas gauge for the batteries as voltage doesn't work very well with lithiums. Also quite useful for diagnosing electrical issues.

[hamm2018]

Originally Posted by NeedToRetire

I just purchased a new Fifth wheel that came standard with a 220 watt solar system. I had on hand two new 100AH Lithium LifePO4 batteries, I intended on installing them in our former TT, but trade it in on the new 5er. I had the dealer install the two 100AH’s instead of the Lead Acid.

We immediately took the new 5er on a three-week trip to warmer places and now back home I have some questions.

1: I today ordered a third 100AH battery to add capacity. At what state should I have all three batteries before connecting them all together? Is it just having them all at the same voltage? As a side note, all three will be the identical batteries and within 3-4 months of age.

2: When the campers not in use in the summer months, should I disconnect the solar? Also, what voltage should the batteries be at before doing so?

3: I am thinking about adding a inverter, just to run light loads like CPAP and TV. The Keystone camper I bought said “Inverter Ready” with some outlets marked inverter. With the current 220W of Solar and 300AH battery capacity, what size inverter would be recommended? I know it’s a bigger load, but with my current described configuration, could I occasionally run the Microwave with the right inverter & 300AH batteries?

4: I was hoping the roof was ready for another 220W panel, but it is not If our intentions are to ocasionaly be off grid 2-4 days, do I just need to bite the bullet and add it now. I'm not in love with monkeying with a brand new warranted roof though. On this 3 week trip, with our current configuration, we went 3-4 days unhooked/dry with no problem.

1) The batteries need to be at the same voltage and % of capacity (SOC).
2) You still have a draw on your batteries, how will you keep the batteries charged while storage if you disconnect the solar? It will also depend on how long you plan on not using the rig.
3) Microwaves are different sizes and power draw, what is the power draw from your microwave. Add up what the power draw will be and go from there. What all do you plan on running while on battery at the same time? Anything else might be added later on?
4) Mounting the panels, using the double-sided automobile tape. Installing another battery, with the same number of panels, it will take longer to charge the batteries.
Before adding more panels, add the battery, then do a trip and compared the two trips to see if there is huge difference.

[NeedToRetire]

Originally Posted by Tony Ramirez

1) I would have the ALL 100% SOC(remember, it's better to look at State of Charge than voltage w Lithiums), then hook them together.

Im not sure how to determin SOC, other than to check the resting voltage?

[TacomaJoe]

Look into your "inverter ready" wiring. There may be just a loop of extra wire feeding those marked outlets. You cut the loop and insert an inverter. Needs to have automatic transfer and feed through function.

Your microwave may not be on the inverter ready circuit. If your panel has a breaker labeled for inverter, you can flip it off to see what it powers.

[NeedToRetire]

Originally Posted by SteveJ.

3] Check your documentation for allowable inverter capacity and specification requirements. A 2000 watt inverter and your 300 AH should run the microwave, assuming proper wiring.

Here's the list from Keystone

SOLARFLEX PROTECT 220 COMPONENTS
Future Solutions 220-Watt Solar Panel
30A Solar Roof Port with MC4 Connectors & 10 AWG MPPT Solar Charging Circuit
30A 12V Only Victron SmartSolar MPPT Controller with Bluetooth app (upgraded for 2024!)
Inverted 110V Loop Prep with Up to 7 Outlets (inverter not included)
Zamp Solar Sidewall Charge Port with 15A Solar Charging Circuit
Batteries not included

The optional 440W Keystone system has a 2000W Inverter

Originally Posted by SteveJ.

4] You could always setup a portable solar setup. This would also give you the option to not park in the sunny areas in hot weather.

This I will do, says it wired and ready for up to 15amps

Originally Posted by SteveJ.

If you do not have one, get yourself a shunt battery monitor. Dry/dispersed camping is so much easier if so equipped. It's like a gas gauge for the batteries as voltage doesn't work very well with lithiums. Also quite useful for diagnosing electrical issues.

It came with a monitoring system app that worked real well called Victron Connect. I used it everyday, to check the voltage. It had a history also, that you can review showing total watts charged & high/low voltage points.

[Tony Ramirez]

Originally Posted by NeedToRetire

Im not sure how to determin SOC, other than to check the resting voltage?

If your batt are Bluetooth, it may tell you. Otherwise, it's easiest to get a Victron Shunt. It tells you how many AHs used & put in, SOC, & other info. Pretty reasonably priced & Bluetooth.

[d23haynes57]

For a parallel connection if you have adequate charge capacity, you can hook them up and they will equalize at full charge.
For Lithium most manufacturers suggest limiting to 4 in parallel. The 100 A/H were probably a poor choice as this limits you to 400 A/H, which really limits you to a 2,000-watt inverter. They will support 3,000 watts for short period. The market currently has the near 300 A/H battereis as the most cost effective sweet spot and some are compact almost fitting in the same space as the standard 100s. Your other limitation is the size of the circuits, wiring, for your "inverter ready" set up. Is it 20 amp, 12 gauge, (2,000 watt), or 30 amp 10 gauge, (3,000 watt)?
Combination inverter/chargers give auto transfer ability and is what your "inverter ready" set up is designed for. The better 2,000 watt units will usually have a 100 amp charger and the 3,000 watt units often go to 150 amp chargers).
The 3,000 is a sweet spot. Microwave, coffee make and maybe even a toaster.
Or, that can also run an AC.
3,000 watt/150 A/H, 600 A/H battery, that is the best overall plan. More capacity for run time can be added later if needed. The 150 A/H charger puts you at a 4 hour charge rate making good use of generator time when needed.

[Tony Ramirez]

If you have Victron Connect, use that to tell SOC. It's the % number.

[NeedToRetire]

Originally Posted by hamm2018

1)
2) You still have a draw on your batteries, how will you keep the batteries charged while storage if you disconnect the solar? It will also depend on how long you plan on not using the rig.

The camper has a master DC switch as well a a switch for the solar. I will be intermitantly using the camper all summer

Originally Posted by hamm2018

3) Microwaves are different sizes and power draw, what is the power draw from your microwave. Add up what the power draw will be and go from there. What all do you plan on running while on battery at the same time? Anything else might be added later on?

Its a 1500w micro. I will not run anything else while using the microwave and will only use ocasionaly/little

Originally Posted by hamm2018

Before adding more panels, add the battery, then do a trip and compared the two trips to see if there is huge difference.

Third battery will be here this week.

[Stircrazy1]

Originally Posted by NeedToRetire

I just purchased a new Fifth wheel that came standard with a 220 watt solar system. I had on hand two new 100AH Lithium LifePO4 batteries, I intended on installing them in our former TT, but trade it in on the new 5er. I had the dealer install the two 100AH’s instead of the Lead Acid.

We immediately took the new 5er on a three-week trip to warmer places and now back home I have some questions.

1: I today ordered a third 100AH battery to add capacity. At what state should I have all three batteries before connecting them all together? Is it just having them all at the same voltage? As a side note, all three will be the identical batteries and within 3-4 months of age.

2: When the campers not in use in the summer months, should I disconnect the solar? Also, what voltage should the batteries be at before doing so?

3: I am thinking about adding a inverter, just to run light loads like CPAP and TV. The Keystone camper I bought said “Inverter Ready” with some outlets marked inverter. With the current 220W of Solar and 300AH battery capacity, what size inverter would be recommended? I know it’s a bigger load, but with my current described configuration, could I occasionally run the Microwave with the right inverter & 300AH batteries?

4: I was hoping the roof was ready for another 220W panel, but it is not If our intentions are to ocasionaly be off grid 2-4 days, do I just need to bite the bullet and add it now. I'm not in love with monkeying with a brand new warranted roof though. On this 3 week trip, with our current configuration, we went 3-4 days unhooked/dry with no problem.

for the first one, ideally they should be the same, but as long as they are with in 0.1V of each other they will be fine. I usaly shoot for 0.05V or less difference but its a little overkill for a full battery. I think the recomendation is with in 0.3 but I think thats a little to wide of a difference myself.

for the second, is your solar controler programable ? what I do with mine is set it to a different program when I am not camping so it only charges to 13.4V, then a day or two before we are going to go caming I change it back to full charge.

If you are not going to run several high loads at once then a 2000watt inverter will handle everything. I can run the outside fridge and the microwave at the same time if I want. but I can't run the microwave and the toaster at the same time, or the toaster and the kieurg. so its a trade off to how you camp. I am not familier with how much power a cpap uses so its hard to say how the 220watts will do, but I imagin with 300ah of battery and the solar you should be able to do a deicent amount of time.

for your last one, you could get portable panels that plug nto the rv and easily double what you have. I have seen up to 400 watt portable kits.. I have also seen people just use ridgid panels, that are intended for the roof mount, just used as portable panels. you just have to figure out how to store them when you are moving. myself personaly, I would just bite the bullet and take it up to as much solar as you can put up there for a reasonable cost. so one 450 watt panel or two 350 watt panels. roofs are pretty much bullit proof as long as you don't snag somthing, just have to do your inspection a few times a year and touch up anything that looks suspect

[hamm2018]

Originally Posted by NeedToRetire

Its a 1500w micro. I will not run anything else while using the microwave and will only use ocasionaly/little



Third battery will be here this week.

You will be surprised what else will be on at the same time. Fridge may be on, plus the load on the 12VDC side from the batteries. A 2000-watt inverter may be okay to use for your requirements.
Add the new battery and see how this charge compared to just 2 batteries. May take longer to charge the new system.

[NeedToRetire]

Originally Posted by d23haynes57

Combination inverter/chargers give auto transfer ability and is what your "inverter ready" set up is designed for. The better 2,000 watt units will usually have a 100 amp charger and the 3,000 watt units often go to 150 amp chargers)

Not being Solar/Lithium savy, should I be looking at a combination unit? Is the benifit additional charging capacity/quicker recharge on shore power? Does it knock heads with the coaches built converter?