eFoil Battery Packs

Have you ordered from Fogstar before? Are they legit? I need some 30q’s.

I bought 500 25R’s from them. Built a 8S4P for my skateboard, a 12s14p for my foil and some other batteries for friends.

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Yes, you can connect two batteries in parallel, each with their own bms. They will balance, and battery with lower voltage will charge at max charge rate that its bms allows. You don’t need additional bms.
If you connect two batteries without bms, each battery at different voltage, you will probably blow or damage one or both batteries if there is big difference in voltage. Energy transfer would happen immediately, and batteries could not handle it.

Perfect -

On a tangent but related note, if the ESC is capable of attaching to multiple cells, does it make more sense to just connect to each cell vs. putting them in parallel? Then the ESC cuts off the specific cell if the voltage is too low. For charging purposes, keep them in parallel so only have to hook up 1 charger…

Hello everyone, I am trying to figure out what type,model of battery and charger would be more suitable and/or compatible for my build, with the parts you can see in the picture that I have already bought. I am not an expert myself, so anyone that has succeded can help. I approximately would like the battery to last up to 50-60mins. Also I am wondering what would be best a custom build one or a premade? I unfortunately cannot order from China or USA as the customs fees are extremely high and my budget is not that big.
However, I have plenty of space on the board for the battery. Please let me know of any cheap batteries and chargers that could work with the build.
Thanks in advance
George , Greece

I have almost the same setup as you.

I use 4 of these (actually on sale right now):

And this:

The charger is good since it charges two batteries at a time and have an onboard powersupply. Takes about 2-3h to charge the four lipo batteries.

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Hey Guys, what do ye think of this?

Would it work?

Or they have:

Price doesn’t seem that bad considering it comes with BMS, Batterys & Charger c/w free delivery to Ireland.

Thoughts?

Any update or purchase links>?

Hello,
I am also looking to make myself a Li-ion 18650 pack:
[https://fr.aliexpress.com/item/33002446800.html?spm=a2g0s.imconversation.0.0.1c8d3e5fYWNVpm](https://fr.aliexpress.com/item/33002446800.html?spm=a2g0s.imconversation.0.0.1c8d3e5fYWNVpm)
at Nkon I have 550 euros worth of VTC6 batteries to which I have to add a BMS 150 amp, a 5 or 10 amp charger, nickel strips…
So my question is do you think this kind of ready-made pack is good?
Is it better if I take a 12 or 14 S knowing that my ESC is a swordfich 300 pro over 15 s maximum?
And for the BMS 150 ampere is it enough or do I have to go on a 200 Amp continuous discharge?

The salesman tells me to use 21700s as a stack for this model:
https://fr.aliexpress.com/item/32983995323.html
What about 21700 batteries???

Thank you for your answers

I used Samsung 30Q’s (120 cells, 12s5p x 2) in one pack configuration. I am working on a board now that’ll be Sanyo 20700B’s (112 cells, 14s8p x 2) in another board. It really just comes down to what you wanna do. Both packs I can add a third pack for extra capacity and amps.

I don’t use a high amp BMS since each pack is wired together in parallel so it’s 60 amps per pack. I am using a Smart BMS now which is great. But really you should look into space and weight as to what works for you. The 20700 cells weigh a LOT more than 18650s.

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Strange, the energy density for the larger cells is 5% lower than the smaller ones. From packaging point of view it should be vice versa. Also the price for larger cells is much higher.

Smart BMS? is this a brand? Can you please provide a link?

If you type in “Smart BMS” on aliExpress I’m sure you’ll find plenty. They make an iPhone app that works with these smart BMS’s I plan to use.

Hey guys,
I’m a new fan of electric surfboards/electric hydrofoil surfboard and fascinated by new technology.
But for efoils battery packs, we did some custom lithium battery pack projects for efoils.

  • Voltage: 43.2V (nominal) (max. 50.4V)
  • Capacity: 35 Ah (1512Wh)
  • High-density and high C rate Samsung INR18650-25R 2500mAh cells
  • Maximum 100A continuous discharge current, 200A discharge current protection
  • High discharge current resistant lithium-ion battery with battery management system(BMS), with UART or other smart communication protocol.
  • Weight: About 9.5kg (Not including the waterproof housing)
  • Runtime: About 40min ~ 50min (Depending on your weight, water surface, speed, skills…etc)
  • Custom Waterproof Housing: IP67/IP68 for options. (Depending on your working envirooment and water depth)
    [https://sapphirehuang.blogspot.com/2019/06/what-is-electric-hydrofoil-surfboard.html]

Should anyone need assistance for your business or looking for another battery solutions? please feel free to contact me to offer you a solution!

Sapphire

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Can you tell us how much this battery pack cost?

Any update or purchase links>?

Hi

What about price? and delivery time?

has anyone seen this before? I woke up this morning to this…after charging

battery%20swell

You are soooooo lucky! Never charge lipo’s overnight and unattended. Those things will burn your house down in a second if allowed to. That looks like it was on the brink of going poof!

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what battery pack do you use?