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Battery + Inverter in a tiny popup RV vs mounting them in a milk crate

max514

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I am looking to power power Starlink internet and charge my laptop when I'm off the grid in my tiny popup camper that stays at our off-grid campsite semi-permanently. The camper has it's own lead-acid battery and power center that powers the water pump and lights and I bring the battery home with me to charge it. The system I want to add is strictly to power Starlink and the Laptop but, if I need emergency power, it'll be there I guess.

My (preferred) idea is to buy a Renogy 100Ah LiFePO4 battery with the direct-connect monitor, a Victron 12/800 inverter, and a Victron 12/15 charger top off the battery between trips. I would permanently mount the inverter with a fuse in the compartment under one of the dinette seats, terminate the wires with an Anderson connector, and do the same on the battery side so I can take the battery with me when I leave and bring it back, charged, when I return. I'd simply drop the battery in its spot, connect the Anderson connectors, flip the switch on the inverter, and connect my devices. In this scenario, I could always add an MPPT and a couple of panels.

This solution makes sense to me but after a lot of reading, it seems like an inverter in an enclosed, non-ventilated space is a bad idea, even if the compartment is pretty large, so it seems like it's not a good (and safe) solution. The compartment is basically a ~4ft long X ~2ft wide plywood box with seat cushions on top. There might be other stuff stored in there but it would never be completely packed. Am I wrong and overthinking this? Is this the way to go? So many videos show huge inverters crammed into tiny spaces with piles of wires and these people are not all burning down their RVs.

Should I just build a portable rig? It seems a DIY in a toolbox is also a bad idea (no ventilation) so the milk crate design seems like the right (but not so elegant) option. I don't love it but it would work. I could simply rig up a battery to an inverter and be done.

I've also been looking at power stations for safety, portability, and ease-of-use but if feels like overkill in terms of the number of outlets and dc ports, which I will never need and I'm also worried about the lifespan of those units. Spending $2,000+ on a Bluetti AC200P, which would be ideal, feels risky. Yes, they use LiFePO4 batteries that will last for thousands of cycles but if anything in the unit fails, I'm left with an expensive brick I can't repair. Therefore, I'm back to my simple setup.

I'm looking for some advice, based on experience. I'm having a very difficult time making a decision because I'm not clear on whether my original idea is actually the right way to go. Thanks for reading.
 
I use a laptop running in a truck for my business for the last 15 years. I have always purchased a 12 volt cord for them. 6 different ones I think. I don’t know about your internet device but look into it as well. Running a inverter costs watts.
 
I use a laptop running in a truck for my business for the last 15 years. I have always purchased a 12 volt cord for them. 6 different ones I think. I don’t know about your internet device but look into it as well. Running a inverter costs watts.
I didn't even know those existed! I'll look into it.

Still leaves the Starlink router which runs on 110. Yes, you can modify the ethernet cable to inject PoE but I'm not ready to dot that... Yet.
 
It's hard to know if you need ventilation until you have the inverter in place and have stress tested it. My Multiplus 12/3000 is in a closet in my RV trailer. I installed it in the winter, so it was hard to tell how much heat was building up. I left the inverter running 24/7 to power a battery charger for my UTV. Now that it's summer, the heat from the inverter is just too much for me to allow. It's not bad, at least not hot enough for the inverter's fan to come on. I added ventilation fans to the closet, but the entire trailer is closed up when it's at the storage lot, so fresh air is hard to come by.

For now, I have the inverter turned off. Starlink is in my near future and that will be one more draw on the inverter. I don't think I'll be leaving the Starlink (and inverter) on when the trailer is at the storage lot in the summer. My understanding is the current version of Starlink has been using around 100 watts, but a newer version will use closer to 60 watts.
 
It's hard to know if you need ventilation until you have the inverter in place and have stress tested it. My Multiplus 12/3000 is in a closet in my RV trailer. I installed it in the winter, so it was hard to tell how much heat was building up. I left the inverter running 24/7 to power a battery charger for my UTV. Now that it's summer, the heat from the inverter is just too much for me to allow. It's not bad, at least not hot enough for the inverter's fan to come on. I added ventilation fans to the closet, but the entire trailer is closed up when it's at the storage lot, so fresh air is hard to come by.

For now, I have the inverter turned off. Starlink is in my near future and that will be one more draw on the inverter. I don't think I'll be leaving the Starlink (and inverter) on when the trailer is at the storage lot in the summer. My understanding is the current version of Starlink has been using around 100 watts, but a newer version will use closer to 60 watts.
So it's definitely going to be too hot under that seat. It's a new RV so I'm not ready to start cutting holes and installing fans. Besides, my wife might kill me.

As for Starlink, a few Redditors say it draws 40-60W on average, without the dish heater on.
 
My (preferred) idea is to buy a Renogy 100Ah LiFePO4 battery
Personally, I would avoid that battery for several reasons.
1. It's very expensive, you can pick up a 12.8-volt 100ah SOK battery for $150 cheaper and that's with the Renogy battery being on a $125 sale.
2. You can't connect these in series, although it's unlikely you would ever need a higher voltage these batteries can last 10 years and your needs might change as your systems grows in the future so it's always nice to not have an unusable battery.
3. They can't be repaired, SOK's batteries can be repaired so even if a cell goes out you can just swap in a new one and it's good as new while if one of the Renogys 16 pouch cells fails the whole battery is useless
4. Many people don't like Renogy as a company, there are many stories on here from them having really bad customer support of having products arrive dead and a lot of people don't like them.
 
You will not have issues mounting the inverter in the enclosed space, the inverter is quite efficient, no load power is 5.6 watts, dropping to less than 1 watt in eco mode. At 100 watt loading the dissipation will be around 15 watts, this is small and will not cause any significant temperature rise in the compartment. Worst case, ( that won't happen) the thermal protection in the inverter will reduce power and shutdown if over heated. The Victron is an excellent product.
Your concept in having a made up system with battery and inverter rather than an over priced 'power station' is a sound strategy.
Regarding the battery, the Renogy is rugged and very well constructed, but as suggested DIY repairs would be difficult. However a number of my 'clients ' have been using this battery with no problems. A major drawback is no Bluetooth direct access to the battery to monitor battery and cell status. I understand you will be adding the optional battery monitor.
There is a very big difference in heat disipation between a 3000 watt inverter charger and a small inverter operating at low power.
The proposed location sounds large at 2 x 4 foot and seat height, I would have no concerns mounting a small, very efficient, inverter in that space, even with other 'stuff' occupying the location. In fact have mounted equipment in similar locations many times. Go with your preferred idea.

Mike
 
Personally, I would avoid that battery for several reasons.
1. It's very expensive, you can pick up a 12.8-volt 100ah SOK battery for $150 cheaper and that's with the Renogy battery being on a $125 sale.
2. You can't connect these in series, although it's unlikely you would ever need a higher voltage these batteries can last 10 years and your needs might change as your systems grows in the future so it's always nice to not have an unusable battery.
3. They can't be repaired, SOK's batteries can be repaired so even if a cell goes out you can just swap in a new one and it's good as new while if one of the Renogys 16 pouch cells fails the whole battery is useless
4. Many people don't like Renogy as a company, there are many stories on here from them having really bad customer support of having products arrive dead and a lot of people don't like them.
I don't expect to connect them in series. The SOK was my first choice, based on Will's recommendation, but in Canada it's $200 more expensive than the Renogy. I'm not stoked about the pouch cells either, nor the horror stories about customer service but choices are limited. After those two, prices jump to $1,200 for a Battleborn and $1,300 for a Victron. For those prices I can get 2 x 100Ah Renogy or 1 x 200Ah Renogy. The only one that is less expensive is the Ampere Time on Amazon for about $30 less than the Renogy. Which would you pick?
 
You will not have issues mounting the inverter in the enclosed space, the inverter is quite efficient, no load power is 5.6 watts, dropping to less than 1 watt in eco mode. At 100 watt loading the dissipation will be around 15 watts, this is small and will not cause any significant temperature rise in the compartment. Worst case, ( that won't happen) the thermal protection in the inverter will reduce power and shutdown if over heated. The Victron is an excellent product.
Your concept in having a made up system with battery and inverter rather than an over priced 'power station' is a sound strategy.
Regarding the battery, the Renogy is rugged and very well constructed, but as suggested DIY repairs would be difficult. However a number of my 'clients ' have been using this battery with no problems. A major drawback is no Bluetooth direct access to the battery to monitor battery and cell status. I understand you will be adding the optional battery monitor.
There is a very big difference in heat disipation between a 3000 watt inverter charger and a small inverter operating at low power.
The proposed location sounds large at 2 x 4 foot and seat height, I would have no concerns mounting a small, very efficient, inverter in that space, even with other 'stuff' occupying the location. In fact have mounted equipment in similar locations many times. Go with your preferred idea.

Mike
Oh wow, thanks! This was unexpected. I appreciate the math behind the heat dissipation. It makes sense to me. The compartment is spacious and the power center the RV came with is mounted in the other one, along with all the wiring, a 20 gallon water tank, and a water pump.

Regarding the Renogy battery, it's not my first choice but it's well-priced in Canada. In that price range, it's between them and Ampere Time. For monitoring, I guess I could add a Victron smart shunt to the mix...

Here's a question for you: my understanding is that the power center the RV came with, a WFCO WF-8725 would only charge a LiFePO4 battery to ~80% but I haven't been able to verify and they never replied to an inquiry I sent over a week ago.
 
I have 3 Renogy batteries. What is the issue, they each have there own BMS and a warranty? In case of a fire in or around your home made solar electric system.... the Insurance company is going to look at your self built battery system and say sorry.
 
The power supply you have will charge to 14.4 volts, that's within the range suggested by Renogy for their battery.
The WFCO operates most of the time at 13.6 volts. This will charge the lithium to over 80%, and long term to a higher SOC.
I see no problem in using this charger/power supply with a Renogy Battery, its not super ideal but is a workable solution to keep the litnium battery at a usable state of charge
It could operate in parallel with existing lead acid battery, a major European builder of expensive RVs uses this technique.
However I would regard this as a short term temporary technique the keep the lithium charged, rather than a permanent instalation

As I commented in the last post, the build quality of the Renogy battery is excellent and, as in your Country, here in the UK, its excellent value, and is on my list of recommended batteries.

Mike
 
The power supply you have will charge to 14.4 volts, that's within the range suggested by Renogy for their battery.
The WFCO operates most of the time at 13.6 volts. This will charge the lithium to over 80%, and long term to a higher SOC.
I see no problem in using this charger/power supply with a Renogy Battery, its not super ideal but is a workable solution to keep the litnium battery at a usable state of charge
It could operate in parallel with existing lead acid battery, a major European builder of expensive RVs uses this technique.
However I would regard this as a short term temporary technique the keep the lithium charged, rather than a permanent instalation

As I commented in the last post, the build quality of the Renogy battery is excellent and, as in your Country, here in the UK, its excellent value, and is on my list of recommended batteries.

Mike
Thank you for the advice and for the time you took to explain. After my original post, I started thinking of swapping the original battery and keeping the WFCO but I tend to do this. I get excited and my small, reasonable plan turns into a big elaborate thing. Sometimes, it's great but in this case, I'll keep the original system for the lights and water pump and supplement with battery + inverter + external charger.
 
I have 3 Renogy batteries. What is the issue, they each have there own BMS and a warranty? In case of a fire in or around your home made solar electric system.... the Insurance company is going to look at your self built battery system and say sorry.
Are you happy with them?

I can see a fire hazard with no-name cheap china cells and a $34 BMS but Renogy + Victron should be safe, no?

From an insurance standpoint, I don't see the difference between branded all-in-one system and a branded battery + branded inverter connected together properly. I currently have an AGM battery (sealed and safe) in my basement that supplies a backup sump pump. It's basically a battery with a power supply/charger unit between the battery and to the wall A/C with a 12V pump connected to it so it can charge the battery and supply the pump in case of a power failure. If that caught on fire, why wouldn't my insurance cover me?
 
I don't expect to connect them in series. The SOK was my first choice, based on Will's recommendation, but in Canada it's $200 more expensive than the Renogy. I'm not stoked about the pouch cells either, nor the horror stories about customer service but choices are limited. After those two, prices jump to $1,200 for a Battleborn and $1,300 for a Victron. For those prices I can get 2 x 100Ah Renogy or 1 x 200Ah Renogy. The only one that is less expensive is the Ampere Time on Amazon for about $30 less than the Renogy. Which would you pick?
Ah, that makes a lot more sense. The Ampere Time while well made does not have low temp protection so if you charge it while it's below freezing it will destroy the battery. There are some charge controllers that have this built-in for this scenario but it's still not ideal. I guess your best bet would be to go with the Renogy one seeing how you're in Canada and it will definitely get below freezing.
 
Are you happy with them?

I can see a fire hazard with no-name cheap china cells and a $34 BMS but Renogy + Victron should be safe, no?

From an insurance standpoint, I don't see the difference between branded all-in-one system and a branded battery + branded inverter connected together properly. I currently have an AGM battery (sealed and safe) in my basement that supplies a backup sump pump. It's basically a battery with a power supply/charger unit between the battery and to the wall A/C with a 12V pump connected to it so it can charge the battery and supply the pump in case of a power failure. If that caught on fire, why wouldn't my insurance cover me?
Your getting homemade out of context for some reason. Yes I like my Renogy batteries no problem.

When you introduce homemade or shop made into an electrical system for your house your taking a chance your Insurance company for no good reason other than they can, refuse to pay for your now burnt down house because what you made was not Listed or Approved and maybe was the cause.

You can or may do as you please, but my sons friend had an issue with a non-UL approved power supply the Ins Co. claimed Could have been the cause.
 
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