Making alternative eppg

What’s your unit weigh right now @Bob27, are you still working on making a unit?

My unit has taken forever as I have been pretty busy this last year with other things, but I just finished the electronics of the 4.5kwh battery four days ago. (still need to make the case) Also since I started building this battery 6 months ago, i found an even better cell which in the same 24s11p configuration will give us 4.8kwh with less voltage sag. I still have the mad M40 43kv motor that we will use for now, but my plan has been to switch to the M50 since we heard it was in development almost a year ago.

Anyways, the final weight is also looking to be around the 76-77 pound range. I might later cut the next battery down to 4.3kwh for a weight of about 73 lbs, but I will see how I like the current weight first.

What cells are you using for you pack then? Because even with a 5000mah cells with lower discharge that’s still below 4.8kwh.

The current cell I am using is a genuine Tesla model 3 cell which gives 4800mah. (I guess I will have the first Tesla powered aircraft :joy:) I built many smaller battery packs ranging from 35 watt-hour to 0.5kWh(the bigger one to test heat build up in a bigger battery pack) and put them through dozens of real world tests on drones which pushed the cells harder than the paramotor would. From that I was able to gather live date as to their temperature, voltage, current, etc. I found that in all my tests the cells would pretty easily give 15 amps continuous while staying cool and would give 20+ amps for long periods at a time with reasonable voltage sag and heat build up. They also left in the dust other high capacity cells such as the LG M50, Samsung 50E, standard non-tesla Panasonic 5000mah 21700, and molicel M50A as soon as the current passed 5 amps. Other cool parts of the Tesla cell included a dirt cheap cost(between $2.50 and $3 per cell after shipping of you knew where to buy them), if properly used they have shown to be capable of 2,000+ cycles (a paramotor pushes them way harder than a car so it wouldn’t be nearly that good, but still better than most li-ion batteries), and they where designed to be self heating as the model 3 has no battery heating system which would be very nice for flying in the winter. (in my testing they would have a very high internal resistance and build heat extremely quickly until they hit about 110 degrees Fahrenheit. After that their AC internal resistance would drop to almost nothing, the voltage sag would decrease, and they would produce very little heat.

I’m not ready to reveal the secrets of my next battery cells, but the cells hold a true 5000mah, and in testing have shown a comparable thermal and current performance to a Samsung 40T. So with this battery I will be able to unleash the full 20+ kW of the mad M50 motor.

You mentioned discharge. Assuming the sp140 uses the molicel P42A cells, then at 110 amps constant it will give about 3.65kWh energy. At the same current, my Tesla pack will give about 4.1kWh and my next battery pack will give about 4.4kWh energy.


You have secret battery cells? Poggers :scream: Are you Elon Musk lol

You just gonna us the molicel M50A then? And why have secrets, don’t you want to share so all the community can benefit? Why hide info?

You should just use the 4.8kwh pack not the 4.4kwh pack.

I didn’t see any pics of you first pack and your already going to the second pack, your going to fast please share the first pack pics first :smiley:

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If you can share your cells, BMS, and construction. I’m looking at building a lightweight pack (30-45min)

at last! now it’s getting exciting :slight_smile: many are currently considering investing in F *** Elon Coins … but it’s top secret! :wink:

I have wanted for years specifically to build and sell E-ppg that would be the same cost as a high end petrol paramotor, but use high quality li-ion cells and high quality motors. So I first contacted my buddy about this in December of 2019. Up until that point, the only high quality E-ppg on the market was the Exomo and Paracell, but they cost nearly $15k a piece. It was only about 2 months after we started talking that the sp140 was first unveiled which would be the first E-ppg to fill this market. Don’t get me wrong, I absolutely love that the sp140 has come out and is bringing low cost and high quality electric paramotors to people and I have pointed dozens of people that want an electric paramotor towards it. On the other hand, I know that realistically I can’t compete cost wise with the sp140 because of how well your team at OpenPPG has done it. So I am scratching for any way that I could possibly improve over the sp140 to validate our higher cost and I think this battery cell that I have spent hundreds of hours finding and am now testing could be the foothold I really need for this business to succeed. My problem is that if others get their hands the battery cell, then this business I have wanted for years has very little chance of making it.:thinking:

I mentioned it before, but the molicel M50A sags bad enough that the Tesla cell blows it out of the water, so it wouldn’t be the smartest to build my next pack out of those.:wink:

I tried to say this previously, just like the sp140 battery pack is rated at 4kWh, it gives about 3.65 kWh energy if under a 110 amp discharge. My 4.8kWh battery under the same 110 amp constant discharge will give close to 4.4 kWh energy. I was trying to compare the energy given by the batteries under a medium discharge current.

This is what the Tesla 4.5 kWh battery pack looked like about a month ago. If you are worried about safety, the highest voltage potential on the battery when the picture was taken was only 7.2v. I’ll see if I have any more recent photos that show it more complete that also look half decent.

Here is a discharge graph of my “secret sauce” 21700 cell compared to a Samsung 40T at 15 amps. We both know that discharge graphs never show the full picture of how a cell discharges when in a pack, but it’s still impressive.

I really don’t mean to be petty. I hope you understand how much I have worked towards this. Also if I am as crazy as half of your probably think I am right now, then the cell I have found would be garbage and not worth sharing anyway.

Well it’s an open source community it probably not the spot for you if that’s your mentally. And if you see us as a competitor like that then can’t really trust what you say here on the forums.

Also like these secret battery cells what’s stopping anyone from just using the same ones, once you release your battery?

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@Bob27 From a customers POV, i would love to see higher flight time numbers with lower weight especially
Maybe you could you be a 3rd party who we can purchase SP140 batteries from (verified by paul or something or not)? Or coordinate/collaborate with @Pdwhite in terms of compensation for your time / business partner / battery supplier, or something, im sure the business world has had and solved scenarios like these in the past you could explore?

Side note to Paul, i love the SP140 and thinking of getting it after i see some positive reviews, but why the load bearing bolt on the gooseneck bars esp when the scout developer did a video on the better way to handle it and i believe i saw the x4 have those better arms? Was a bit disappointed to see that, but i have a nitro200 with the same bars that seems to have been ok for now…
Also any chance of offering a magnesium vs aluminum frame later on in case of a crash so we can bend it back?


What would you suggest I do Paul? I respect the work you have done in building your company, how open you are, and the amazing products you have created. I really do want to see E-ppg move forward as a whole, but how do I balance that with business? I have tried to be as open as I can in spreading my knowledge while leaving any business ventures of mine out of this and trying not viewing OpenPPG as a competition. You can see dozens of occasions on this forum where I have encouraged people to get an OpenPPG sp140 or x4 over a different option because that was best option for that specific person.

Also like Denisz mentioned, I am sure there is some way we could work together. Heck, we are going to be using the same motor with the same voltage and as long as our batteries have the same connector, they would likely be fully compatible with each other. Based on this I know there is some way we could work together to help bring E-ppg to everyone.

Ya i would love to just be able to buy the battery’s from a 3rd party, especially if they are lighter weight and provide longer life and flight time. I looked and i could not find any off the shelf battery’s so that’s why we had to make our own, and that’s obviously a lot of work, and cost can go up if its only used for one product.

I don’t care who or where a product is coming from as long as its the best quality and price. So I would be happy to solely just get packs from Austin if he can bring the specs and cost he is talking about. I would just stop making the other packs in a heartbeat. But i obviously need some sort of display of is performance, then if its good that could be the new SP battery.

As for the goose neck bar bolt, at some point the bolt is just as thick and strong as and aluminum pivot. And right now the TI bars will bend before the bolt for the pivot would break. Like you could go to a 12mm bolt and then you have 2x the strength, but at the loads needed to break it you looking at 70 plus Gs of force if the pilot weights 200lbs. So like many other parts would fail before that bolt does. At the Ti bars right now are the lightest solution while providing torque compensation. Also a big reason we used the CNC strait aluminum bars was because they are easier to manufacture then the 3d bending welded titanium bars. So the TI bars take more up front investment but are better long term.

For the frame as it is an Aluminum alloy it can be bent around a bit but, not indefinitely. So I think if long term frame strength is a concern, iv been thinking about just offering free unlimited replacements frames, just shipping would need to be paid. My goal is just to make the frame so robust and low cost that we can do that. And that would also cover all the Sp140 that are already out there. Just need to get a bit more data on it right now.


Bob If you can assemble and ship a batteries for the X4 you’ll have a small market for it and potentially push X4 sales too. I’m sure many would reconsider the X4 with the availability of a convenient, more robust (than Bonka LiPos), pack ready to mount and plug in. Since the BMS is built in that should reduce the cost of chargers too. Could you create an adaptor to plug into an EV charging station?

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Wowser! How awesome is that!

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Random thought. My partner is a paramotor frame manufacture and has just wanted to have an electric option for his paramotor, but the only way we could get that was to develop an entire system from scratch. You seem to have developed a pretty solid system. Would you be interested in providing us with the electronic systems? In turn we could then put more of our time and resources into developing this battery and getting it into production faster.

Ya there are quite a few people that want to convert there current frames to electric but the biggest thing is the frame is really out lowest cost component. So really only a 200-300 would be coming off the cost. And being that most frames out there are around 1000usd if wanting to be bought by them self’s its hard to make that method worth it.

And like who is your partner? I hope its not a secret partner lol.

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Not going to lie, I have been working with Flat Top Paramotors. Dell can be quiet the character at times although in person he is awesome to talk to. Anyway, his nephew Trevor is running quite a bit of the business now and he is pretty level headed and down to earth.

Do you know roughly what we could buy just the ESC, throttle, and battery for? Of course we would hope to be building our own battery in the next few months.

The problem is that it would be a really small market. We would need basically every X4 owner buying the battery to be able to make them in a quantity were it could be profitable at all and not cost the X4 owner a fortune at the same time.

I can completely understand if you do not want to supply Flat Top Paramotors with components. Flat Top does have a reputation that Dell gave us which we are trying really hard to fix, but it is still there and likely will be for a long time.

But like Dell is still the owner right, did you and Trevor buy him out or something. Like if you are trying to fix the reputation it really doesn’t seem like it. I haven’t taken a look at the flat top channel in awhile, and all it took me is 30 seconds to take a look and it seems like the same stuff as before on a recent vid.

So with Dells “logic” im a “freaking evil murderous scammer” :grinning: Just because i don’t fly a flat top lol.

Its just sure, you don’t have to like tucker, scout, aviator, or whatever but what are the chances that you don’t like any of the 50 other paramotor/schools out there. Until I see some sort of change in thinking or action I don’t want to work with or be associated with that and i would be surprised if you wanted to be also.