Novel Nissan battery pack

[JamieGeek]

This is interesting: Nissan will be selling the "Roam" a battery pack for campers made up of "used" EV batteries:
https://www.engadget.com/2019/02/18/...mping-trailer/

[Chance]

Jamie, do-it-yourself repurposing of Nissan batteries by guys with lots of electrical knowledge and experience does not seem that uncommon, so maybe something you may want to look at also.

A friend and I were looking at option of buying Nissan battery modules to assemble a 48-Volt battery, around 10kWh in capacity, and it came out to around $200 per kWh for the used modules. To that you have to add cost of battery management and all connection hardware to connect a bunch of modules in combination of series and parallel.

There is risk involve though. If modules are old they may not perform well, and if newer but from a wrecked car they could have damage. Regardless, it’s an idea we are still thinking about in combination with 48-Volt inverter/charger.

The power unit in your post, if accurate that it’s only 700 Wh, seems pretty large for what’s no more energy than a common RV battery at roughly 50% discharge. I’m not sure what you get beyond installing an AGM in the trailer and using a small inverter. I suppose portability is a plus, so when done camping it can be taken inside house. Or at campground you can move unit away from RV to power devices. Not something I personally find very useful for our kind of camping.

[99dart]

I got to thinking about used battery modules last summer. Not being an electrical guy, I was wondering what it would take to use a "battery pack" from a Ford C-Max like my wife drives. Would it have to be taken apart and reconfigured into a usable size voltage? Or, could it be reduced electronically? It seems like the RV world could use a new source of battery power like this. Lighter, faster charging... I only know enough to drive myself crazy with questions! LOL

[JamieGeek]

Originally Posted by 99dart

I got to thinking about used battery modules last summer. Not being an electrical guy, I was wondering what it would take to use a "battery pack" from a Ford C-Max like my wife drives. Would it have to be taken apart and reconfigured into a usable size voltage? Or, could it be reduced electronically? It seems like the RV world could use a new source of battery power like this. Lighter, faster charging... I only know enough to drive myself crazy with questions! LOL

Well there is this: (They took a Tesla battery module and put it in their RV)

https://www.youtube.com/watch?v=g_cC0NKvCDY

[Chance]

Thanks for video, it’s very informative. I did not know how Tesla batteries were configured.

Two of those Tesla modules in series would be just about the right size — about 10 kWh at ~ 48 Volts. He mentioned already having a 24 Volt Inverter/Charger, but I can’t see using 24V on a new system when 48V seems to be the future.

One of the advantages often mentioned about using Nissan Leaf battery modules is less sensitivity to cooling and heating. The video, however, mentions that at low power levels (likely encountered in RV use) that cooling shouldn’t be required. That’s really good to know. Keeping a battery from getting too cold is much easier than having to cool it down during high-power utilization.

Economics is still a big issue for me unless the RV just can’t handle the extra weight of lead batteries, or you have to be able to recharge really fast. In his case the 5 kWh usable battery capacity could be accomplished with about 300 to 350 pounds of lead batteries if one is willing to replace them more often. And they are safe, simple, and easy to replace anywhere at any time.

There is a lot to consider. One problem is that if you custom build a unique system, how is that going to affect RV resale? Would the next owner want to rebalance battery every couple of weeks, or cover with a heated blanket like mentioned in video? And even if everything is automated, how would the next owner handle any malfunction?

[JamieGeek]

Funny thing about battery heating and cooling. When I searched for that video the following video also popped up. Note that here they are using 5 battery modules and are using a fish-tank heater to keep them warm in the cold ! LOL

https://www.youtube.com/watch?v=Fcg7FuiUB9I

[Chance]

Jamie, the Nissan Leaf air-cooled modules appear to me much easier to rearrange in whatever size battery bank you want. It seems many are going to 7 modules in series to make about 3.5 kWh capacity at 48V nominal (up to 55V fully charged).

You can buy these already assembled on eBay but expect you can build your own also.

[Chance]

Or you can install multiple units in parallel for greater energy capacity. A problem I see is that connecting for 12V doesn’t seem as practical as the 48V option.

[JamieGeek]

Interesting, not sure I'm at the point where I want to put EV batteries in the coach.

It is an intriguing option.