Lithium batteries.

[ShuttlePilot]

Wrinkledpants, All true. I apologize if I sounded as I was questioning your decision. I agree we are nearing the point that to not have a lithium battery in a new van would be viewed as old tech. I was just hoping they would be offering a bit more storage at that price. In addition to the advantages of Lithium you mentioned, I notice your in Denver and here in Colorado Springs when my lead battery is 10* cold it's real hard to coax power in or out of it.

Wowbagger, That's awesome. Way more storage than I need in my van but, awesome. One of my off grid friends has a system around your size for their house that they just switched to Lithium. It's a small house and theirs is one of the smaller systems but it fits their needs. Which dose lead to the question, can you actually have to much storage capacity?


This is from a friends ridiculously large off grid system. These are 24 2volt lead acid batteries. Capacity? dunno. it's a lot.

-Eric

[Wrinkledpants]

Ha - I didn't think that. Just answering your question

Keeping the batteries warm is the primary issue we're looking to tackle in regards to the electrical system. Most of the AGM's I see are mounted under the van in the cold. The lithiums need to be mounted somewhere where you can keep them warm, which means inside. So, even though they take up less space, your usable space in the van is reduced because the batteries are now in there.

Will be talking with SMB about an insulated compartment under the van that has access to coach heat, or has some type of heating pad under them.

SMB's price is installed. You could definitely do a lithium setup for much cheaper on your own.

If you consider the cost of 2 4D batteries, solar, and a generator - the cost of lithium doesn't look too bad. Consider the fact that the Hydronic 5D heater is a $7k option and all that does is heat your water and air. Something propane does at a fraction of the price.

[adstewart91]

While not in production now, self-heating Li-Ion Batteries could be a thing of the future:

From:
https://www.sciencedaily.com/release...0120141537.htm

"The researchers, relying on previous patents by EC Power, developed the all-climate battery to weigh only 1.5 percent more and cost only 0.04 percent of the base battery. They also designed it to go from -4 to 32 degrees Fahrenheit within 20 seconds and from -22 to 32 degrees Fahrenheit in 30 seconds and consume only 3.8 percent and 5.5 percent of the cell's capacity. This is far less than the 40 percent loss in conventional lithium ion batteries.

"The all-climate battery uses a nickel foil of 50-micrometer thickness with one end attached to the negative terminal and the other extending outside the cell to create a third terminal. A temperature sensor attached to a switch causes electrons to flow through the nickel foil to complete the circuit. This rapidly heats up the nickel foil through resistance heating and warms the inside of the battery. Once the battery is at 32 degrees Fahrenheit, the switch turns off and the electric current flows in the normal manner."

[LenS]

Self heating? Lithium batteries have been doing that for years. Hoverboard manufactures and the airline industry have known about this phenomena for a long time.

[reelchef67]

Originally Posted by ShuttlePilot

Did someone say Lithium?



I say do it and be a pioneer. Just remember that being the pioneer there will be a steep learning curve, possible set backs, might not work the first turn of the key, could cost a lot of money, but the adventure will be awesome
If your not into that sort of thing the AGM route might be better.

Please keep us posted on what you decide and congrats on being in the planning stage of a new van.

-Eric

if even of those batteries shorts internally it will turn the entire pack into a bomb. Ive used lithium batteries in rc vehicles and had it happen . I also had a flashlight with 1 18650 batteries in it that exploded the aluminum casing causing a fire. the flashlight overheated fater being left in the sun on a porch. I would never trust a homemade battery pack with my life . .

Just my .02 cents
stay safe

[AndrewInSeattle]

Why does SMB require a 2nd alternator to support Lithium? Is that a fundamental requirement, or just a nice-to-have so it charges at a reasonable rate while driving?

Our power use will be modest without A/C or microwave, so we ordered our Sprinter without one, but I'd like to keep the van future-proof if we decide to upgrade to Lithium once the technology is a little more settled.

There's probably still time to change the Sprinter order to add the 2nd alternator if warranted... ah, the benefits of a long waiting list, we can keep second-guessing everything for more than a year!

[Wowbagger]

The charging parameters of lithium batteries are just enough different from lead acid that having a separate alternator makes things much easier - the voltages are different (LiFePO4 is 3.5V per cell for 14.0 volts, normal vehicle is 13.8V), LiFePO4 can take much more current when discharged and could overload the main alternator, a few other things.

[Wrinkledpants]

Originally Posted by AndrewInSeattle

Why does SMB require a 2nd alternator to support Lithium? Is that a fundamental requirement, or just a nice-to-have so it charges at a reasonable rate while driving?

Our power use will be modest without A/C or microwave, so we ordered our Sprinter without one, but I'd like to keep the van future-proof if we decide to upgrade to Lithium once the technology is a little more settled.

There's probably still time to change the Sprinter order to add the 2nd alternator if warranted... ah, the benefits of a long waiting list, we can keep second-guessing everything for more than a year!

I would order the Sprinter with the 2nd alternator bracket. I think it's quite expensive to do later on as there are a few coolant lines that need to be replaced/moved. It's only $400 or so from mercedes if you order it that way.

I have a phone call with SMB on tuesday and will get some more details on the lithium setup they're going with.

There are other ways to charge lithium without having a 2nd alternator, but from what I've been able to research, they're usually more complicated or end up with much less power. One of the main benefits of lithium is that they can take a big current all the way to full charge. So, if you have a dedicated alternator, you can charge the lithium batteries in a short period of time.

We're now considering bumping our battery size a bit to 4 or 500 ah, and not having solar at all. We could idle the van for 20-30 minutes a day to top up the batteries. If we do solar, it's just going to be a single panel for the times when the van is parked for a week or more and we want the fridge running. With a rooftop AC unit and 144 length sprinter, roof space will be a premium for gear. The 3rd option we're looking at is no solar and using an auto-start that will turn the van on at a certain battery voltage.

[Wrinkledpants]

Just to update this thread, I had my PC with SMB West and they said it was south that had the lithium option, but details on the setup were few. Seems like the various SMB dealers all do things a bit different, so West wasn't sure if they would use whatever their setup is, or go a different route. All the SMB dealers are having a meeting in the coming month or so where they share ideas and plan for the future, and I guess that's where they'll iron out some details on the lithium setup.

I know someone in this thread mentioned leaving their lithium plans with SMB south, so I'm guessing it's similar to that setup, but really have no idea. SMB West did indicate they would rather have a lithium setup that's established, rather than buying the individual pieces. So, something like lithionics or Victor where all the parts come from the same manufacturer.

They'll happily install whatever we provide them, and at this point, we're leaning heavily towards Lithionics. They seem high quality, have everything from the alternator regulator to the battery, and their batteries come in a variety of sizes.

Will keep this thread updated as we move along, or as SMB solidifies their lithium plan.

[LenS]

Here is a great thread on batteries. "Gary RV Roamer" has some excellent comments and I personally have much respect for knowledge on the subject. He posts on th RVForum site.

12 V Batteries-Planning for Full-time