Move to Lithium

[Neal]

Maybe email Newmar and see what the price is. On some stuff it's not bad, others it's a total gouge. [email protected]

 

[Richpatty]

I ended up buying the gasket from Newmar…. At least I could by it by foot and it was free shipping. It worked well to seal my battery compartment door, but don’t feel like the new gasket that they are selling works as well on the electric cable chase…

 

[Richpatty]

Ok, and is anyone interested in a slightly used battery tray? I also have the straps and clips which are in surprisingly good shape.

 

[Richpatty]

Quick update: We are out on our first RV trip since completing my Lithium upgrade, and although this is a not a boondocking situation, I have been trying to use them as if we were... Basically, the charger has been off since Thursday and we have not fallen below 65% (or so) SOC by morning. We have had very good sunshine and even hit 1376w coming off the panels (of a potential 1440) the other day. I believe the good numbers are somewhat due to the Lithium's being so hungry and able to pull all the power the panels have to provide. And with the sunny days (even with a few cloudy mornings) we have always recovered to 95-100 SOC by late afternoon.

We have even used it to cook dinner with our toaster oven twice. I have not run the AC off of them yet (I have the ability to run one from inverter) but will test that on our way home. Overall, I am really happy with them and have become a bit geeky looking at the Victron app all the time (I know @Neal and @Chuggs will appreciate that). I have also been happy with the SmartShunt. Its Bluetooth is a bit week, but it is a handy device and provides nice data. And it is usually within a few percent of the Magnum SOC, which is good as well.

I can really see how people would like having the Lithium's

Thanks
Rich

 

[Neal]

Awesome! Great to hear (I think...batteries coming soon for me).

 

[Jim]

Yes, this is an awesome report! I've been wondering how your conversion went, sounds like a success!

 

[Neal]

OK! I FINALLY got some time (over the course of two weekends) to complete my Lithium conversion. It went pretty well, but it was more time and effort than I expected. I would say the effort was comparable to my solar installation.

The rebuild of the battery compartment took some effort. As I had mention in my plans, I removed my battery tray, cleaned out the compartment and added 1 inch insulation and 1/2 plywood (which I painted white prior to installing). This was challenging, but it makes for a much more sealed and nice looking compartment. I ran the insulation up to the top of the compartment to seal it off the best I could. I added foil insulation tape to close it off at the top.

Summary of the changes/improvements I made (in no particular order):
- I re-used the 3/0 cables that Newmar had used for the batteries for the short connections between the batteries and and the runs between the banks of 4.

- In trying to best balance the charging and discharging of the batteries I used a method which breaks down the 8 batteries in 2 sets of 4 and has the negative and positive leads come off separate sides of the bank. I attached a picture of an example.

- I added busbars for both the positive and ground connections to make connections easier and more standard.

-I moved my Victron solar controller from the first storage compartment to the new battery compartment to make it easier to get to and also shut down when needed (my RV has a covered port which stops the solar).

- I added (finally) a new cutoff switch to shut down the 12v in the RV. This will help with parasitic loads when stored.

- I added a small (2x10) floor vent to the back of the compartment for ventilation in hot weather. It can be closed (like any floor vent) for winter. I also have a magnetic sheet that will go over it to help seal it when I want. I also have plans to put two computer fans on the back of this vent (12v) and set them to a thermostat to run when the temperature becomes warm.

- I purchased/installed a Victron Smart Shunt so I can see SOC via Bluetooth. I wired my Magnum shunt receiver to the Victron Smart Shunt (although I removed the actual Magnum shunt) so the Magnum will still be aware of (and calculate) the SOC.

- The new batteries are held in place on three sides by 1 1/2 aluminum L-bar. I also added 1/2 hard foam insulation between the batteries and the bar to make sure there are no ware points as we bounce down the road. I added insulation between the two banks of four to also avoid rub points, but also to add space for the cables that run to each battery. I also added a strap for each row of batteries to hold them down.

- I will be installing a Lithium BIM in the next week or so as an insurance policy. I am not really worried about losing any charge time from the alternator (due to the Li-BIM) as I have the solar to depend on. Also, the Lithium's charge pretty quickly, so you would not have to be on shore power or generator to top them off.

I think that is it... I will post something else if it comes to mind.

The finished product is below.
I am glad it is done!

Rich
View attachment 11279
View attachment 11280

@Richpatty what did you end up using to connect the batteries (cables / bars) and where did you get them? Did you build them yourself or have them made to specified lengths? Compartment looks great, as you mention, this looks like quite a bit of effort. I'd move my victron equipment in there too after seeing what you've done and get it out of the slideout bay adjacent. I assume the magnum 2812 is fine or are we losing anything with that inverter? If spending this much on 8 x Lithium batteries should the inverter be considered?

 

[Richpatty]

@Neal, after much thought and debate, I ended up using cables instead of bars…as I realized I could reuse the cables that Newmar used to connect all of the LA batteries…. I bought new 3/0 lugs and cut the cables to the needed length. Between the connecting cables and the 3/0 cable they used to connect the batteries to the ground (which i replaced with 4/0) I had enough to make the 12 short cables to connect the batteries together.

And I agree on moving the solar controller….MUCH more convenient.

As far as the inverter, everything stayed the same…as the new lithiums are just adding capacity so the inverter doesn’t know anything changed. The inverter would be another investment that I didn’t feel I needed to do at this point. Especially considering that if you go much higher in inverter wattage, you may start to exceed the breaker panel it is feeding. Bottom line is I was happy with it, but if it every fails, I would replace with Victron….

Hope this helps.
Rich

 

[Neal]

So if you're going to redo the battery bay is there any reason to go with GC2 batteries? I would assume that form factor is to have a drop in replacement for LA/AGM GC2's. In hindsight, would you still recommend the GC2 or go with a different battery?

The Victron batteries look interesting but not sure how they play with the Magnum inverter. I was looking at battery options on AMSolar.com

Lithium Battery | Lithium Batteries | Lithium Solar Battery Bank

When you need a drop-in lithium battery for your RV, AM Solar has the top dependable brands including Battle Born and LifeBlue lithium batteries.

amsolar.com

 

[Richpatty]

I agree that if you are going to rip out the tray, it does not matter which battery size/config you choose. I liked the GC2s because of their battery terminals as well as their cost per amp hour. Their size also allowed me to be flexible with how they were installed and the foot print they would take up.

That being said, if they had a larger battery that was cheaper per amp hour, I may have chosen it…

And I am sure the Victron batteries would be fine. My goal was to get one with a proven track record and someone who would stand behind them. They also got good reviews from Will Prowse, who rips these things apart for fun…

https://youtube.com/c/WillProwse

Hope this helps.
Rich