Dual Carbon Battery

[bruce.markle]

Gents û

FYI; a company in Japan ôcloseö to producing a 400 WH/KG battery called
ôDual Carbonö.

(100 mAH/g = 100 AH/Kg; x 4 volts = 400 WH/Kg. And Non-Flammable.



Current state of the art is 250 to 260 WH/Kg.



http://powerjapanplus.com/battery/equation.html



Also, at the CafÚ Electric Flight Symposium, Qichao Hu from Solidenergy,
an A123 Spinoff, is working on a Solid Polymer Ionic Liquid (SPIL) battery;
also non-flammable. Capable of 250 to 450 WH/Kg, doing Gen2 of it now which
is 300 WH/Kg and about improving cycle life, Gen3 will be higher power
density in summer 2015.

[earthstaraircraft]

Cool!!

Sent from my iPhone

[ejbnorfolk]

For those of us not up to date on these parameters, how does this compare with what Mark is currently using?

thanks
Ed B

[bruce.markle]

Current “best state of the art” LiPos are in the ballpark of 250 KWH/KG. This number when you see it quoted would be for a bare cell, without a case or rigid mounting structure, and would be without wires and circuitry of any kind. So if they come up with some 400 KWH/KG battery, what would have been 100 lbs of raw batteries will now weigh only 63 lbs.



There is data on the Zero battery packs in the photos section of this website. According to it, the [largest] Zero 11.4 KWH battery pack (which I think is the one Mark is, or was using) weighs 77 Kg, so the pack will come in at 148 KWH/KG. [For some reason the table also has the weight energy density listed as 130 KWH/KG; so either the capacity of the pack is wrong, or the weight, or the energy density number]. This 148 KWH/KG would not be expected to be the 250 KWH/KG even if it used those bare batteries since there is other stuff in the pack that will make it heavier (circuits, wires, and a support structure, maybe cooling). They also may derate the actual capacity of the pack somewhat to get a longer lifetime as the cell capacity degrades with use. Just guessing, but would estimate the raw batteries embedded in the Zero pack (maybe 2 years old at this point) would have been around 200 WH/KG, with the degradation down to 148 KWH/KG by adding the items above…



Regards

[rahulchoudhary73]

Thanks for sharing, Bruce. Very nice. Pure carbon chemistry ought to be way more value for money than others, also lighter monitoring & support structure, being non flammable

rc

[earthstaraircraft]

Hi Ed
My current battery's produce 134 Wh pr kg.
Happy Flying
Mark

Sent from my iPhone

[ejbnorfolk]

Wow. That would be quite a bump up in capacity ... 400 wt/kg versus 134 wt/kg
The pace of change in batteries is amazing.