Battery Search For Efoil Build

Hi all, I just joined this forum, I am a high schooler doing an Efoil build as a project. I recently purchased this kit from Flipsky: Group W7 Water Sports Kit (Includes High Current FSESC75300 /75200 and – FLIPSKY

I was wondering what battery I should use for this, if you can send links, that would be greatly appreciated.

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That is great school project!!

I’m new to this so I don’t feel qualified to answer your question but many here have a lot of experience.

I would suggest you provide some more detail on which motor and VESC you chose in that package along with what some of your design criteria are - run time, weight ,expense, build or buy etc.

There are lots of threads here that discuss this issue so also encourage you to read about the many options available.

These are the options that I chose when buying the kit. I’m looking for a battery that is 72v, 20ah. I’m probably going for around 30 minutes of ride time. I want to stick with it being under 500 dollars probably.

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Why do you want a 72v Battery?

Be careful, batteries declared as 72V deliver peak 84V (20s) and will fry your VESC
The 75300 is for 18s max
Trampa rates it for 16s max to allow for spikes.

Most used Batteries with the 65161/65162 Motor here are 14s or 12 s, more than enough to get foiling.

If you buy a battery pack don’t go to low on Ah, otherwise the pack will not be able to deliver the necessary A, depending on the cells used in the pack you need a certain amount of parallel series. And cheap packs = low current even with many parallels

I build a battery pack of 12s6p Molicel P42A which gives me at the moment 55 min of pure ride time. As I fall frequently I suppose ride time will get even better when I have less starts.

I got everything I needed to build the battery pack, including Cells, Ni strips, cables, connectors, smart BMS, shrink wrap etc. and even the spotwelder incl. LiPo for 500€ (and hours and hours of study). But beware, building a high power battery pack is dangerous an can set your house on fire

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I could add that in water 60v max is the admitted safety limit. For Li-Ion, building a pack greater than 14s (x4.2V max = 58.8V, “s” for series) could be deadly if you have a leak current in water. It is for this reason that commercial brands have adopted the 14s battery pack. When they want a lighter battery, they just decrease the capacity (Wh) in their “nano” range by decreasing the “p” number (parallel) eg 14s14p to 14s7p.

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Thank you for the help! If you don’t mind, can you send me the link to all the parts you used for the batteries, and do you know if they would ship to the US or if they’re only for the UK.

What do you know about this company It looks like I could just build a battery here, do you think I can trust this?

Hi dreznik I have used:
Molicel INR21700-P42A
Cell Holder 1326p cut down to 12s, but they have also 14s
Pure Nickel Strips 0.2 mm and doubled the series connection
Smart BMS 120A UART

Kapton Tape, Cable, Anti Spark XP90, Shrink tube in 260 and 400 mm from Ali

Mini Spotwelder from Amazon, modified according to Luca
3s 5000mh LiPo from Amazon

My battery was determined by the size of the case: I use a Max300s Case strapped to my Wingfoilboard (the Max004s I bought first was not waterproof - fortunately I testet it beforehand).

Last ride was 13.85km (1h of fun). As I have to drive 3h to lake Garda and back I now will build a second battery pack to double the fun

There are a lot of battery builds here in the forum and in the eskate forum, and many better than mine, so continue studying. Plan first, buy later.

And be careful, there is a lot of energy in these packs: If you accidentally shorten cell blocks with a piece of Nickel strip falling down on your pack it just will glow and melt down if you’re fortunate. If it is thicker like a screwdriver or even just a screw your pack might start to burn If you don’t remove it fast enough!

As to voltaplex, I can’t tell you.