Yes usually, but also 14s
Today I set a personal record.
Huge range! Looks like the power required for 30 kmh is roughly 3500W, this includes all the energy loss( mainly heat?), so actually engine output is somewhat less.
Was out for your record today, but had to stop with 17% battery left. Was riding in nice evening swell. I loose the feeling in my feet after 60min. Then my kid started calling like crazy, so i had to stop.
I think I migjt be able to tie you Robert with my 8p magic battery. Just need to loose some more weight and get below 70w/km…
16S 100kv 7”FR Veloce M/surf stab.
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It seems to me that the battle now begins…. 
What’s your weight?
And tell me please something about your magic batteries.
I regularly get 1h20min ride times and average 20 miles range.
Here’s a quick 1h10min 15 mile ride I did recently. Good waves. Nice solo surf session.
Im 100kg, so fighting to get same efficiency as you with gong setup.
Not really magic battery, but very compact for its energy. Im using 16s8p samsung 50E crammed into a max04 box. It gets quite hot as this is not high discharge variants.
Just had a new record for me with my new battery (14s10p P42A)! 17miles (27km) in about an hour (to a completely empty battery, I swam the last little bit in when it got below 3.0V a cell). My gross estimate of efficiently is 110W/mi (68W/km) with slingshot 84cm wing.
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What have you set as voltage cut off (per cell)? And as voltage cut off start (per cell)?
I had it set to 40 or 42V (~3.4-3.5V a cell for 12S) to start the cutoff and 36-38V to end (~3V a cell for 12S). I swap out 12S and 14S batteries so I don’t have an easy way to change the cut off. So I just monitor my remote until I am near 46V (3.3V) and come in, after 3.3V a cell it drops really quickly.
3.3-3.5 is a good start of cutoff and 2.7-3.0V a cell is a good end of cutoff.
Did a long run on my happy foil and 14S, efficiently was way worse, but I was going about 19-20mph the whole time with a couple runs hitting 23mph. Battery lasted about 40 minutes and I went 12.2 miles.
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Hi! I’m thinking of purchasing a Flipsky 65161 motor and I’ll be using it with the flite prop. Should I build a 12s12p, 13s11p or 14s 10p battery?
…10p will allow a very short cruise time, the battery will drain very quickly. I think cruise time is the most important parameter of the e-foil propulsion system, so it is better to increase the number to …14p. I am planning 13s20p (or 14s20p).
Weight and max current are also important parameters to tetermine the battery. More capacity means more weight. Batery pack max current depends on the individual cell max current and number of parallel cells. Number of S depends also on the KV of your motor and max speed you want to achieve. If you want to run it without bms, an even number is better because you can split them into two 6 or 7S packs. If you use high current 18650 cells like samsung 30Q, everything from 12s8p to 14s 16p works. With 21700 cells like molicel p42A even 12s6p would work. Personally, I would not go above 14S 40Ah nominal capacity (2000wH). This results in a 10kg battery. As a reference—I use a 12S8P pack (split in 2x6S8P) from MolicelP42A with a 63100/130KV motor, a flite prop and RL wing. Max speed is 40km/h, range is almost 19km @69Wh/km. Total battery weight is 7kg, riding time around 50min.
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Depends on 18650 or 21700 battery also. I have a 12s12p 18650 Samsung 30q and a 14s10p 21700 p42a battery. Both work well but the p42a has more energy for a longer ride.
14s20p is huge and will be a beast of a battery in both weight and ride time. Probably the biggest pack that I’ve seen on here. I prefer to be able to swap batteries and keep it lighter.
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Yes, I agree, for a regular e-foil (e.g. v1) a low battery weight is better. However, I’m building a slightly different concept of e-foil - in it the battery will be placed firmly, without the possibility of pulling out - the goal is to achieve a cruising time of 2 to 3 hours.
However, it is possible that I will need a smaller battery, maybe just a 13s16p. The number of parallel cells will depend on the parameters of the propeller and wing, which I will design myself. So the main goal is to get the longest cruise time possible, so that I don’t have to wait for annoying recharging after a short cruise, and so that I don’t need another spare battery.
Interesting 20p , I was happy with my 8p12s already , conception choice is challenging with other limits : motor and controller running for hours and the legs !
However, a larger number of parallel cells also has the advantage of reducing the discharge current per cell and extending cell life. I don’t mind the greater weight of the battery because I don’t find it important to pull the battery out for each charge, just as I don’t pull the battery out for an e-bike, e-scooter, cell phone, laptop, etc. etc.
But you will need a trailer to put it in the water. If you have to carry it, every kilo counts. Everthing above 25kg is not really convenient to carry, especially a bulky thing like an efoil. Unless you want to do really long rides, the battery should not be more than 10-12kg, complete board without battery can be built to weight around 15kg.
I think I can achieve a maximum weight of about 25 or 26 kg (battery: 13 x 18 x 46g = 10764g). I am trained to this weight with daily use of the e-bike and e-scooter. But as I said, I am building a slightly different concept of e-foil. Its advantage is also that it doesn’t mind too much the higher weight of the battery. Unfortunately I can’t explain or show the concept in detail yet, as I may have it patented for the whole EU first. All I can reveal now is that the concept is a bit close to an e-foil type sniper rifle holster, but hydrodynamically and aerodynamically quite ideal.
Well a sniper rifle holster goes on the back, so I’m starting to think that you just strapping the battery to your back which has already been tried… Not a good idea though…