li battery pack of my dreams

[pianotuna]

Now, if the cold weather problem were solved.....


https://www.rj-lithium.com/sale-12037443-48v-500ah-lifepo4-25kwh-battery-built-in-bms-factory-price-...

I don't know the price.

Nominal 51 volts 500 amp-hours (25 kwh). Maximum continuous draw 100 amps surge 600 amps (bms shut down current).

[2oldman]

pianotuna wrote:
I need something that can survive -40.

Is the place you keep your batteries actually that cold?

[pianotuna]

Valhalla,

I need something that can survive -40.

[ksg5000]

2oldman wrote:
562 pounds? I don't think so.

x2 - weighs as much as a wood stove.

[valhalla360]

pianotuna wrote:

Sticking points are r... cold weather operation.

Actually shouldn't be a big issue unless you are trying to heat with electric (unless you get to really extreme cold).

The big amp-hr use is typically the air/con, which you don't typically use when it's cold.

[2oldman]

Not sure I follow. You comparing 12v to 48?

[pianotuna]

2oldman,

I'm not average. I find 556 amp-hours is not nearly as nice as the 875 I had before.

[theoldwizard1]

time2roll wrote:
Looks small for the capacity. Must be the advantage of pouch cells instead of the cylinders.

Pouch cells, often called LiPo (lithium polymer with polymer being the pouch) can be very dangerous. As they charge and discharge, they heat up. As they heat up the pouch expands. If there is not adequate room for this expansion, "bad things" can happen !

LiPo tend to use LiCo (lithium cobalt) chemistry and NOT LiFePO4 chemistry because LiCo has higher "energy density" (more power per ounce).

[Boon_Docker]

There is another brand for $26,000

Link

[pianotuna]

Why I said of my dreams.

I want lots and lots of storage 25 kwh would allow me to run the RV as if it were plugged into shore power.

Sticking points are recharging, cost, and cold weather operation.

I don't have a price but apparently this company is about 50% of the Battleborn pricing.

[Yosemite_Sam1]

time2roll wrote:
Half? I was thinking two of them 😉

You might be well ahead in the RV EV conversion.

[time2roll]

Half? I was thinking two of them 😉

[2oldman]

I'm sure it's an amazing battery for its intended use, like on a yacht. But it's overkill for the average RVer. A Prevost maybe with 3 airs.

Imho an ideal size would be about 1/2 that... 200ah or so.

[wa8yxm]

The 51 volts is a tad much for RV use less you do major rewiring or use a dc/dc converter But... cut it down to a 12 volt pack you'd have about 1/4 the weight and 1/4 the watt hours Sounds good to me.

[Itinerant1]

Yosemite Sam1 wrote:

time2roll wrote:
pouch vs cylinder is just that... the shape. Pouch is just in the form of a rectangular box. Nissan uses the pouches in the LEAF. Pictures on the link.

Which packs more power with the limitation of size and weight?

https://batteryuniversity.com/learn/article/types_of_battery_cells

Summary from the article..

•Cylindrical cell has high specific energy, good mechanical stability and lends itself to automated manufacturing. Cell design allows added safety features that are not possible with other formats (see BU-304b: Making Lithium-ion Safe); it cycles well, offers a long calendar life and is low cost, but it has less than ideal packaging density. The cylindrical cell is commonly used for portable applications.
•Prismatic cell are encased in aluminum or steel for stability. Jelly-rolled or stacked, the cell is space-efficient but can be costlier to manufacture than the cylindrical cell. Modern prismatic cells are used in the electric powertrain and energy storage systems.
•Pouch cell uses laminated architecture in a bag. It is light and cost-effective but exposure to humidity and high temperature can shorten life. Adding a light stack pressure prolongs longevity by preventing delamination. Swelling of 8–10 percent over 500 cycles must be considered with some cell designs. Large cells work best with light loading and moderate charge times. The pouch cell is growing in popularity and serves similar applications to the prismatic cell.