Today's RV time?

oosik · May 24, 2021

I don't understand enough of what dragoneggs posted to ask an intelligent question.

caver · May 24, 2021

When I buy a trailer my standard mods are 2 Trojan 105 6volts.
A Bogart Engineering battery monitor.
Blue Sea marine type switch to disconnect batteries
Fantastic vent to replace factory joke fan. (Fantastic got bought out and I hear it isn't the company it was so i found a fan that bolts into the existing joke fan)
Small computer fan in propane reefer to circulate air (new camper it did not seem to help so will probably take it out)
Detachable power cord unless it came factory with one.

dragoneggs · May 24, 2021

oosik said:
I don't understand enough of what dragoneggs posted to ask an intelligent question.

Don't feel bad... I didn't understand what I just said when I started the project!

orezok · May 24, 2021

We’ve been trailer camping since ‘95. Only on our second trailer. First lasted 16 years and the “new” one turns 10 this week!. As we get older, our boondocking days are over so Lithium batteries are expensive and unnecessary. The trailer has become more of a guest room during the pandemic but we will still do a number of 10 day trips a year.

An interesting fact is that we bought the trailer 10 years ago for $18K +/-. We just rewrote our auto policy with the same company we have been with for almost 50 continuous years and they determined the value of the trailer is now $23K. Apparently they use some type of database to determine value. I’ve NEVER hears of a trailer that appreciated over 10 years. The good news is that the premium only increased about $50 a year so I’m good to go.

dragoneggs · May 24, 2021

ponytug said:
I would love to learn more of the details of your conversion. (He says, selfishly.)

All the best, Peter

You are welcome to pick my brain... FWIW. If you want to take something offline you can PM me as well.

dragoneggs · May 24, 2021

orezok said:
We’ve been trailer camping since ‘95. Only on our second trailer. First lasted 16 years and the “new” one turns 10 this week!. As we get older, our boondocking days are over so Lithium batteries are expensive and unnecessary. The trailer has become more of a guest room during the pandemic but we will still do a number of 10 day trips a year.

An interesting fact is that we bought the trailer 10 years ago for $18K +/-. We just rewrote our auto policy with the same company we have been with for almost 50 continuous years and they determined the value of the trailer is now $23K. Apparently they use some type of database to determine value. I’ve NEVER hears of a trailer that appreciated over 10 years. The good news is that the premium only increased about $50 a year so I’m good to go.

It is a crazy RV market this past year. Supply and demand is driving up the values significantly. Also the shortage of parts/components/appliances for new OEM builds is putting additional pressure on the used market.

LittleBill21 · May 24, 2021

dragoneggs said:
On Solar... my RV now has a modest 520W of monocrystalline panels on the roof. I removed the two OEM 100w flexible panels because of the degradation of the fiberglass under them due to the direct contact and heat. The new rigid panels are stood off the roof allowing some breathing room under them.

For the energy storage... I removed the two lead-acid coach batteries and swapped them for two 100watt hour, LiFePO4 (lithium) batteries. This more than doubled my storage capacity since you can run your lithiums down to near zero unlike a lead acid where you start damaging it below 50% SOC (state of charge). The batteries have a built in BMS (Battery Monitor System) but I decided to add a app driven BIM (Battery Information Monitor). This allows me to easily know the state of the battery and i can quickly understand what is the current draw in real time for anything I am powering in the RV. This also will estimate days/hours of battery life and will update as my power usage changes.

A few other 'tweaks'... I swapped out the convertor for one that is lithium compatible. OEM unit would have sufficed but this allows me to fully charge the batteries from shore power or the on board diesel generator.

For best 'communication' between the new lithium batteries and the chassis battery and alternator I added two components. The first, is a Amp-L-Start that allows the lithium batteries to keep the chassis lead acid battery topped off without over charging. Note that Lithium batteries have a slightly higher voltage. The other component is a DC-DC charger that protects the alternator from damage as the Lithium batteries will suck as much current as they can and have the potential to burn up a standard sized alternator.

Been a fun project and I'm very happy with the results so far... will allow me to go unplugged much longer and I won't have to run the generator as much making for quieter camping.

pretty sure you meant 100 amp hour

dragoneggs · May 24, 2021

LittleBill21 said:
pretty sure you meant 100 amp hour

Yep typo... fixed. Thank you.

dmccarty · May 25, 2021

I have been looking at solar, chargers, inverters, LiFePo, etc., for use on a boat we would like to build. Same system would work on the house though not sure it makes money sense.

Any who, be careful with "lithium" batteries. There are different lithium chemistries used for "lithium" batteries. Many of these lithium chemistries will burn and burn and burn. Putting out a fire in these batteries is problematic. The only lithium battery I would use for the house, boat, or even an RV, would be LiFePo chemistry. They are not supposed to burn.

If one has an existing battery system using lead acid, lithium batteries are NOT a drop in replacement. One has to change the charging voltages and times. A regular alternator can be burnt out quickly if charging of the lithium batteries is not controlled/limited. A lead acid battery will self limit how much power it can accept when charging, LiFePO does not self limit. It will basically take what it is given. Alternators in many vehicles are not designed to produce their rated output for very long and they can burn out under the charging load using LiFePo.

Many of the LiFePo batteries have internal controllers to protect the battery. The controllers can disconnect the alternator from charging. If this is done, and there is not another battery connected to the alternator, the alternator is gong to get fried.

Victron and Mastervolt sell integrated components, including alternators(though there are other sources and sometimes better ones), LiFePo batterers, BMS(Controllers), chargers, inverters, etc. These companies are selling to people going off grid, meaning boaters, RVers, and houses.

"Lithium" batteries are a game changer if living off grid. Expensive up front though.

Later,
Dan