Thank you for your reply. Ok then, seems like I need to get to know to configure the ESC via VESCTool.
Instead of custom build battery with cells etc. I was thinking about to use 2 of theseTuning 20.000 mah - 12c. I have seen that on a build here. What is your opinion about?
I will definitely go with a waterproof motor. The one from flip sky seems to to be perfect for my skills/budget.
Best regards,
Umut
I would highly advise against using the 12C lipo batteries. They are not a safe option for our use. After a few uses they will become puffy and dangerous.
For a similar price you can build a 18650 pack.
I had the same (bad) experience. Spend hundreds of euro’s on several lipo’s. Used then 5 or 6 times until they started to puff badly and became VERY hot in the box of my board. For the same price I purchased the cells I needed for a good 18650 pack, which I did in the end. You need some other stuff but there is ample documentation to build these things. It is kind of fun!
Never had any issues with the 18650’s, I can pick the pack up straight after foiling as they don’t get very hot at all.
In addition to all the fail cases solved in the New 200A Vesc based Flipsky ESC thread . For a smooth and more silent running, choose FOC mode detection with sensorless motor.
hello all you legends
long time listener, first time caller
i am researching a build also but have a more immediate project which requires a some battery making skills - you guys have been pretty $%$#$ inspirational in this regard. i would be keen if any one could recommend a good seller of the samsung 30Qs, and a reco for a decent spot welder (i was thinking of a spot welding pen, but would i be wasting coin?).
the elecs are daunting but i navigate through with baby steps - carbon work is more my thing. your community here makes everything seem very doable.
thanks heaps and keep this thing going.
Cheers,
Dan
If you’re in Europe, the best quote should be here mentioning efoil.builder:
Here you have:
I can highly recommend the Malectrics spot welder. It works well. Far better than a lot of the Chinese rubbish available.
https://malectrics.eu/product-category/arduino-spot-welder-bundles/
Cheers, gents.
Any Alibaba or Aliexpress suggestions for 30qs? Am from Aus
Cheers, Dan
Dan be very careful buying batteries from AliExpress or Alibaba. There are many fake batteries out there. I’m currently looking for a new supplier in Australia too. A few suppliers are having difficulty getting stock at the moment. The cheapest supplier I can currently find at the moment is in Perth.
$7 20 per cell
https://www.lanplus.com.au/index.php?route=product/search&search=Samsung
You will need to email them to get a bulk order price.
Where in Aus are you?
Thanks for the info, I am in Perth. I will explore them further.
Thanks heaps, cheers, Dan
I decided to go NOT with the 12C LiPo batteries but actually I would like to buy a pre-built battery pack, rather than welding my own one. I have read some descriptions and I respect the process to much.
What is your opinion with `this pre-built battery pack?
I am just concerned about the 48V. If a battery has 3.6 x12S should be 43,2 V right? It is also possible to ask them for a customization. Has anyone experience with pre-built battery from AliExpress or even did buy customized one?
Best regards,
Umut
Hi Umut,
it’s 13S - maybe your ESC can handle it.
Very hard to say anything about quality - with this the chinese are “individual” 
Mike
Most of the time classic cell like 18650 nominal voltage is 3,6-3,7v , but charged is 4,2v so no problem with 12s you will have 48v
Ok, maybe I will build my own batteries. I have found this gem on Youtube! I think this is a must see for every DIY battery builder and I want to share it with you. The guy is explaining it very reasonable for a newcomer like me.: Don’t use BMS!
Would you agree with him?
Best regards,
Umut
I have designed a 12s6p battery pack based on 14s14p pictures of @Flightjunkie. I will use two 12s6p.
Here are the wiring diagram. Could please someone double check it?
Also I am a little confused regarding the BMS. Shouln’t it be 13 cables? 12 for the cells and 1 negative (1 battery pack). @Flightjunkie is using 8. 7 for the cells + 1 negative. Can a BMS with 7 cables in my case handle that?
Best regards,
Umut
Attachment:
ISTR @Flightjunkie was not using a BMS, but much like i do, uses a balance charger.
You get more control and better balancing with one of these. BMS on the discharge is expensive for the AMPs we use. As long as you trust your ESC fail safes. You can eliminate the BMS entirely.
This allows me to charge only to 4.1v using my ISDT T8 charger. (many more charge cycles due to being much better for the batteries)
Hi.
Looks like a good start on your battery build!
I suggest not using a BMS. I don’t use a BMS.
But, the types of BMS I am familiar with all required the extra wire. Number of cells plus one.
Sorry actually I meant balance charger instead of BMS. Im thinking to get an iCharger X6.
On the wiring diagram the “BMS” stands for the connector which will be plugged into the iCharger X6.
What confuses me though is, that the balance charger will recognize the 6 cells.
Best,
Umut
I’d love to know exactly what it is about the chemistry that makes them so much less reliable. I’ve got four of these large lipo’s. Two have inflated and just don’t feel safe, the other two are doing pretty good. With a charge cycle or two nearly every day for a little while now. Haven’t yet built 18650 packs with this kind of current drain application.
My internal measurements for the bad packs is up to about 3ohm compared to the healthier packs hovering around 1ohm. Not sure where the safe margin is or what caused it. Could be over stressing during early build stages or simply not having been stored well for an extended period by the previous owner on those packs. They don’t get excessively hot but it still scares me enough to not use them.
Or is it that the package of 18650 simply hides these types of things?!? And that they see similar internal increases. Anyhow, curious as to the causes and why’s 
