Consumer-report on a Licerion battery over Venus

My aeroplane for co-efficients has 0.5 lift (c_L) and 0.015 drag (c_D). It runs 70 km over Venus where the air-density (ρ) is 0.09 and the wind-speed (v) 100 ms^-1. Given that, it must discharge 675 watts per square meter of wing, to its turbine. I have already ascertained that 20%-efficient solar is NOT a cruising-altitude power-source at this pace. Solar does work at half that speed... until the plane goes into night. At that point the plane needs an on-board power source. So let's talk about rechargeable batteries.

Assume four days out of external power. For stored energy, that needs 64800 watt-hours times the wing-area. Eventually I want to bring a telescope, so I demand to stay over the vitriolic clouds where ρ=0.09. Besides I don't want my plane to dissolve when I'm in it.

Sion Power (after abandoning Lithium Sulphur) are promoting a "Licerion" promising 650 Wh/kg and 1400 Wh/L (pdf). That is mass density 2.15 kg/L; the same unit as gcm^-3... or tonnes per cubic metre. It compares well with a hunk of light silicate rock.

To pick the one emerging technology I could find which published comparable data: IBM "seawater" offered minimum 800 Wh/L energy density. Also 10000 W/L power density, 90% efficiency, max 300 s to 80% charge. I assume it's about as dense as Sion's.

At 100 ms^-1 up here Licerion would add 100 kg per cubic meter of wing: 864 Newtons / m². It takes up 46 cubic meters of space which can distribute among the wings. Double that if we're allowing eight days.

1/2 ρ v² = 450. To hold up 864 Nm^-2, is needed c_L * 450 Nm^-2. The lift coefficient must surpass 1. LOL! Fortunately I'm plugged into the Flotilla so I don't care.

At 50 ms^-1, 1/2 ρ v² = 112.5. I'm fighting much less drag: at a 0.015 drag coeff, 2.53 Nm^-2. About 50 Wm^-2 would power through that. (By the way, IBM's power-density would allow 200 m² wing... per liter of battery. Or 200000 per cubic meter. I am most NON-worried about power density here. And wait 'till we introduce capacitors.)

This battery, four days out, has used 4860 Wh / m², only requiring 7.48 kg / m² = 64.8 Nm^-2. This minimum lift co-efficient is 0.576.

When we add the mass of the turbine and the equipment, Licerion alone cannot lift a 0.5 c_L, 0.015 c_D aeroplane at 70 km over Venus for four days. But it comes close. For instance Licerion can easily power my vessel for TWO days, with cargo. Licerion is already enough for an untethered plane to enter distress-mode: by which I understand, one or two days drifting back before some rescue-tug rides in for a rescue.

For our plane we're looking not to exceed 5.19 kg / m² = 45 Nm^-2. To overcome 4860 Wh / m² drag: a 936 Wh/kg battery would do it. If we had, oh, 1000 Wh/kg: we could easily squeeze four days from this vessel, and have mass to spare to carry actual freight.

Unlike with 50+% efficient solar-cells I do not consider a 1000 Wh/kg rechargeable power-source to be unobtainium.

ALPHA 1/26 - hang on a moment. Given that IBM is claiming for the seawater battery, a power density of 10 kW/L: if we assume density density of 2.15 kg/L... that's a specific-mass value. α = 0.215 kg/kW.