Monaco lithium battery upgrade

[afelsoci]

I am going to upgrade my Monaco Monarch 30 se to Lithium batteries. Looking for most cost effective way to change charger ,inverter and dc-dc charger. i purchased 2ea Lion energy batteries so far

[Timaz]

I use a Renogy 40 amp DC to DC charger.

[windsorbill]

Originally Posted by afelsoci

I am going to upgrade my Monaco Monarch 30 se to Lithium batteries. Looking for most cost effective way to change charger ,inverter and dc-dc charger. i purchased 2ea Lion energy batteries so far

Without knowing what inverter/charger you have (some are compatible with lithium) , or if you have solar, it's difficult to give you the most cost effective way.

The only reason you need the DC to DC charger is to charge the new batteries from the alternator. Some have gone a different way and rely on the solar to charge the lithium if not on shore power or generator.

[afelsoci]

I purchased a progressive dynamics 60 amp lithium battery converter and a remove 20a dc-dc battery charger. I have 130 amp alternator. Looking at 2000 watt inverter from lion energy. Just thought do to all the labor I will pay to install all of this maybe there is a all in one unit

[afelsoci]

I bought reboot 20 amp . I read that is what I need due to having 130 amp alternator

[Persistent]

Originally Posted by afelsoci

I am going to upgrade my Monaco Monarch 30 se to Lithium batteries. Looking for most cost effective way to change charger ,inverter and dc-dc charger. i purchased 2ea Lion energy batteries so far

The lowest cost method is to reset the existing built in charger to a Li compatible charging profile and to disconnect engine charging.

Late model RV chargers typically have a Li charging profile. Older models do not. Some older models will work with 200 amp hours of LiFePO4. Get make and model of built in charger and check with Lion for best advice. Performance of the batteries may not be optimum. 10 year old model chargers are hopeless. Replace them.

There may be performance benefits to getting a new built in charger. One is a purpose designed charging profile. Getting proper cell balancing at the end of a charge cycle is important for Li battery performance.

Two is getting a higher capacity charger. A 100 amp 12 volt charger will probably charge 200 amp hours of Li batteries twice as fast as a 50 amp charger.

Lithium battery manufactures usually prohibit charging lead acid batteries with their lithium batteries on the same circuit. Charging lithium house batteries from the engine alternator at the same time as charging the lead acid start battery is forbidden.

A 200 amp hour Li battery bank can draw more than 100 amps from an engine alternator. This will over heat a 130 amp engine alternator, especially when the engine is idling. A B2B charger with a Li charging profile can be connected to an engine charging system. It will limit the charge current and prevent overheating.

When a Li battery bank BMI disconnects while charging for one of many reasons, the alternator can spike a very high voltage, destroying 12 volt electronic including alternator controls engine computer systems. A cheap voltage clamping device can be connected to the alternator to suppress the possible voltage spikes.

[shootist]

A friend charged lifepo4s for 10 years with nothing but a simple wet cell charger. I added two timers in series on the ac side after he forgot to shut the charger off. He put them in an electric car and charged them as many as three times a day. You shut lithiums off when they're charged, that's all there is to it. With lifepo4s it's 3.5 volts per cell. Over that is nothing more than a surface charge and baked batteries. They prefer 80% charged so if you're off on your timer setting it doesn't matter much. Also on the long side they'll go to 3.65 and it takes a long time over 3.5 to get them there. It's not the big mystery it's made out to be . So if you want to get by for awhile on your old inverter you can. It's just not automatic.

[Rocketman3]

Here is a list of the changes I have made around batteries. (Yes I know mine in not the budget method), just to help make sure you don’t forget something.

Here are the changes I made.
Before Lithium batteries:
Added a Victron BMV712 Battery Monitor.
Replaced Trace inverter with a Victron 12/3000 Multiplus inverter/charger. (The Trace was having problems)
Added 800w of solar and Victron mppt 100/50
Added Victron CCGX to control Multiplus and monitor everything

A couple years later my batteries died… (also going full-time) so…
Built 544ah lithium battery- (eight Lishen 272ah cells). Batrium BMS
Swapped Victron 1000amp SmartShunt for BMV712
Took out battery charger isolator - so alternator cannot charge/overcharge lithiums. (Broke the connection).

Later changed Refrigerator to Residential so…
Added 400w of Solar and Victron mppt 100/30
Added a Victron 30a Dc-Dc charger so alternator can charge Lithiums on drive days.

In process of adding another 200w of solar to the 100/30 array (over-paneling to help with non-ideal solar days. Needed because Starlink uses lots of power.

The big things to remember is Lithium’s like being charged differently- so ALL charging sources need to be compatible (and you don’t want to blowup your alternator).

Good Luck!