New Samsung Battery Showcased: 20% Shoter, 50% Higher Capacity Than 18650 Battery

Qes

Hey people, Check out this new article that popped up. Samsung shows new battery back based on modules. Link here: https://futurism.com/samsungs-new-electric-car-batteries-boost-range-to-600-kilometers/ Second link (you can find in the first article but is more detailed): "Samsung SDI also displayed cells and modules based on the new 21700 standard of cylindrical battery. A ‘21700’ battery is 21 millimeters in diameter and 70 millimeters in height. Its capacity is 50 percent bigger than the existing 18650 battery (18 millimeters in diameter and 65 millimeters in height). Its size is optimal for maximizing capacity, life and output simultaneously. The new battery beats batteries of any other size in light of cost competitiveness. A 21700 battery draws attention from major global manufacturers as the next-generation standard which can be applied to all sorts of products including electric vehicles, ESS and electric tools." https://futurism.com/samsungs-new-electric-car-batteries-boost-range-to-600-kilometers/

Horsefly

So it is 3mm bigger in diameter, and 15mm taller. How is that shorter? (Assuming "Shoter" was a typo, otherwise I don't know what it means)

So the volume of a 18650 cell is 66,162 cubic mm (pi * 18 * 18 * 65), and the volume of a 21700 cell is 96,981 cubic mm (pi * 21 * 21 * 70). That's about 47% more volume, so yeah, it is about 50% more capacity. Doesn't seem like a breakthrough to me.

Marc Kurth

Yep. advancements are accelerating with new, bigger-better products emerging.

My approach is to see how it shakes out before investing my customer's money. I prefer to let other folks test the "bleeding edge" of technology for me. (Been-there-done-that, have the T shirt)

There is a whole lot of good stuff coming very soon.

Marc

mvas

This was originally announced in January 2017.
Samsung has yet to begin mass production <= yawn.
Telsa is already mass producing the 21700 cell ( since June ? )

18650 cell = 250 KWH / kg
21700 cell = 300 KWH / kg

The 21700 cells do have a higher Energy Density,
they contain 20% more energy per the same weight.

Tesla says,
The only real difference between the 18650 and 21700 is increased size for more active material.
40% more active material per kg = 40% more capacity per kg

BB.

There is the old rule of thumb with math... When you have a 3 dimensional object, the volume goes up with the cube of the dimensions, and the surface area (outside of the battery) goes up with the square... I.e. a 20% "longer/larger diameter battery" would:

• 1.2 * 1.2 = 1.44 more surface area (case)
  
• 1.2 * 1.2 * 1.2 = 1.728 more volume (active material)

However, for off grid power (homes, cabins, etc.), typically we are not too worried about volume/weight of the battery (other than initial shipment/installation issues)--So if the cell is "more expensive" per kWH of storage, it is not really "interesting" for off grid use even if smaller/more dense than other designs.

-Bill

softdown

Lithium technology presents a winning argument when weight is a large consideration. Other than size, weight, charge characteristics, and longevity....I still believe in lead for most solar applications. Lithium is darned expensive and life tends to realize significant changes within 15 years. Such as moves...

Sometimes they juice up the specific gravity and call it a high performance battery sold for more money. Since that decreases the longevity, it is misleading in some ways. 

mvas

BB. said:

There is the old rule of thumb with math... When you have a 3 dimensional object, the volume goes up with the cube of the dimensions, and the surface area (outside of the battery) goes up with the square... I.e. a 20% "longer/larger diameter battery" would:

• 1.2 * 1.2 = 1.44 more surface area (case)
  
• 1.2 * 1.2 * 1.2 = 1.728 more volume (active material)

However, for off grid power (homes, cabins, etc.), typically we are not too worried about volume/weight of the battery (other than initial shipment/installation issues)--So if the cell is "more expensive" per kWH of storage, it is not really "interesting" for off grid use even if smaller/more dense than other designs.

-Bill

Horsefly did the math in message #2 - old volume vs new volume.
( He incorrectly used "diameter squared" vs "radius squared" but for the ratio of the volumes, it does not matter ) 
The 21700 cell is 1.47 times larger volume, not 1.728 larger as you claim, vs the 18650 cell - which relates to mAH capacity.
They increased the battery volume by ~47% ( not ~73% )  and so 21700 has roughly 50% more mAH capacity vs 18650.

In my message #4, I discussed Energy Density ( mAH per kg ) - not mAH capacity.
They have also increased the Energy Density by 20% - ie now weighs less per same mAH capacity

I am very concerned with both weight and volume.

A 48 Volt 17 KWhr Lead Acid Battery Bank 30% DOD 7 year ( if you are lucky ) system consisting of ...
24 @ Trojan L16RE-2V batteries = 16' long shelf and it weighs 2,800 lbs !
$9,360  = $390 x 24 batteries
Now add $ for a 48 Volt 100 Amp 3-Stage Charge Controller, with EQ mode
Now add $ for a 5KW DC-to-AC Inverter
And you have to maintain the electrolyte every month for life, otherwise they will fail early.
You are "married" to this battery bank - hydrometer readings, EQ cycles, distilled water, etc ...

The Power Wall 2 is 14 KWHr, 2' W x 4' H x 6" D wall hung, 276 lbs with a 8 - 10 year guarantee
$8,000 - includes AC Inverter and DC Charge Controller

Someone needs to find a mistake in the above information,
otherwise I see no advantage using Lead Acid Batteries vs Lithium Batteries.

BB.

I was not saying that the battery was 1.7xxx larger volume in this case... I was just trying to demonstrate how surface area increases with the square of the dimensions, and volume with the cube with random numbers--So things become "more volumetricly efficient" the larger they are (same type of issue with small bar refrigerators vs full size refrigerators become, overall, more efficient the larger they are).

-Bill

jonr

From Wikipedia:

Energy density is the amount of energy stored in a given system or region of space per unit volume. Colloquially it may also be used for energy per unit mass, though the accurate term for this is specific energy. 

mvas

Elon Musk was speaking colloquially ...

Mangas

So far, I'm staying in the "most" category.