[Dmatz]

David

Congrats on your new ride. I know you looked for a long time. Many happy and safe miles good to see you here as well,

[Richard]

I have made some upgrades to the coach to provide full sine wave and to gain the ability to program the charge profile I want to the charger to accommodate the LiPo batteries. I am going to add a bunch of detail on what I have done, because I suspect that other RV guys wanting to do a LiPo conversion will be searching for RV specific info.

As a starting point 4 1000aH 3v cells are installed in series to provide a nominal 13v 1000aH battery bank. The bank is installed with a Housepower MiniBMS with one contactor installed on the positive side for both load and charge. A Junsi cell logger is also installed to provide easy reference to cell voltages. The Junsi is not used to alarm or trigger any relays at this time.

I installed a Magnum full sine 2800 watt inverter charger with the Magnum ME-ARC and Battery Monitor Kit. The ME-ARC gives a tremendous amount of flexibility in setting up charge profiles. I have chosen a Custom Profile with the following specifics. Charge voltage 13.8 volts. Maximum charge amperage 200 A. The charge can be set to cut off on State of Charge. Right now I have the charge ending at 90% SOC. I have the charger set to Silent, when the charge is through, therefore there is no float voltage. The charger is set to come back on at 13.0 volts. I have the inverter cutoff voltage set at 12.4 volts. With the charge to 90% SOC and recharge at 13.0, I am operating the system between 30 and 90 % depth of discharge, and each cycle produces around 600 amp hours.

I am not worrying with the alternator setup at this time. I have the coach wired so that the alternator does not charge the house batteries UNLESS I manually activate a merge solenoid. I think this is a great setup for an RV since I don't have to worry about mixing the chassis lead acids and the house LiPo's in a charging scheme. But, in case of need I can easily charge the LiPos with the alternator in a pinch.

My thinking is two fold in these settings. One, the charger is setup to operate well within the high and low cutoffs in the Battery Management system. I prefer to think of the BMS as the insurance policy for the battery bank. Two, there is speculation that operating the bank in the middle of the Depth of Discharge (DOD) prolongs the life of the battery.

None of this is going to mean beans to those who aren't interested in the battery technology. What I have learned in playing with this would have gone a long way to maximizing the AGM batteries I did have. There is a future guru seminar in Batteries at the next rally that will help all with managing the battery bank, the second most expensive maintenance item next to tires. I learned an expression that I like. Batterys don't die, they are murdered.

[pairodice]

Thanks for posting all of this info! I am deciding now whether to go full-bore on a LiPO system or wait until I murder my lead-acid batts :-)

[encantotom]

i think most of us would say wait till you need to spend the money on bad batteries unless it is just burning hole in your pocket.

tom

[folivier]

Also consider your usage. Do you plan to dry camp frequently? That is where the LiFPOs really shine, 80% safe discharge, HIGH safe discharge rate, FAST recharge rate. All of that will cut your generator usage. But at a cost....

[Richard]

I haven't reported in a while on the LiPo system. There is nothing new to report. They work, they work very well. The cells are still in balance to .003 volts, and I haven't touched the parameters since the install of the inverter charger this spring.

[n10s]

I haven't reported in a while on the LiPo system. There is nothing new to report. They work, they work very well. The cells are still in balance to .003 volts, and I haven't touched the parameters since the install of the inverter charger this spring.

I am only reviving this thread to say a hearty "Thank you!"

As a future (hopefully soon) Newell Owner, doing my "due diligence" (cultural/lifestyle immersion and drooling) and aiming to "buy my third motorhome first," your thoughtful sharing of your RV experience with LiPo is absolutely priceless and deeply appreciated!! Though much time has passed since your and others foray onto the cutting/bleeding edge of this innovative technological life solution, very little practical, critical and applicable information is available in the RV domain for newbs like me. I envision upward of 80% of my future full-timing will be in boondocking or dispersed/dry camping situations, with solar (if i can find a feasible way to get it onto the newer designed rooftops, sans shadows).

Anyhew, THANKS, again!

[ROBERT BLAIR]

Any update on your Li battery performance and life?

[Richard]

They are still working. I did not capacity test them when I bought them used
From
Forrest and I haven't capacity tested them since. So I can't quantify if there has been a degradation in performance.

[Doug Musick]

What lithium battery retailers would you recommend today?  Balqon seems to be out of business.  I like the design of the GBS batteries sold by several retailers, but they are definitely "retail price" and seem to Max out at 400 amp hours, which would require multiple battery banks and the additional wiring and equipment that would entail.

Any recommendations would be appreciated.