This must sound irony but I am in China trying to build my first board and it is not so easy finding the right parts. Ps: I had one already but not built by me.
Right now I am looking into batteries and there are many great deals in taobao but they never specify the discharge rate and as I don’t speak Chinese it is also not so easy to search.
The guy from which I bought my first skateboard, an amazing good board for just 250€ and none of you would believe how good it is but I give it to my brother.
The guy says he can build me a battery 10s5p with this battery 21700 5C discharge 4000mha for 113€ without bms because his boards Max to 6-9s so he don’t have one he only welds batteries for me.
I can also buy this by spending 40€ more and saving 20€ if I am buying myself the same batteries instead from him. So for 140€ I can get a welder that can do 0.2mm and all the 50 21700 for my build.
What do you think of the 21700? I have heard they can actually do around 20A and I would have 20Ah capacity with a 5p build.
My build will be dual 170kv 6374.
Here is the Welder also, what are your opinions? The bms I still need to find one. Acceleration is my goal, it is the best part of skateboarding but I wont be crazy doing drag racing, here in Tianjin is all mostly flat as flat gets xD
This is just the first one I found, it’s a Chinese made here from China, 21700 is a Chinese model I read.
if I buy I will do it from a seller with reputation where many other people already bought.
And here they don’t sell abroad, they sell for their own people and scamming the people on the same country is much more risky than sending fakes overseas. I think so. Everything I bought here in taobao for the price and quality I was never unimpressed.
I found one with 40A discharge anyone knows these ones? Converting the price is around 2.2€
A) be in China (you have that covered) so you have legal recourse
and
B) have tools that can verify the capacity and monitor the cell temperature during controlled discharges to verify they are real immediately upon receipt
I don’t know if you have B
Furthermore, withhold payment until you’ve verified you got what you ordered
For 40a even I without much experience with batteries was expecting but I thought i should just shared it.
I still didnt give it enough research. I also want to ask some friends at work for their opinions probably if they are into electronics they must know something.
I need some time until I have a top 3 batteries I can directly buy here then I post here again and we can really discuss about it ;D
But like I was saying before, selling to foreigners or selling inside should have a big difference. I would like to find a tool which can make a full test on the batteries. My ideia is to order like 5 different batteries from 5 different shops and run all 5 throught the test.
Samsung INR18650-30Q are so good and cheap and so easy to get and have verified suppliers, that there is little to gain in trying these cells, over just using 30Q (or maybe 35E for > 8P packs)
Easy to get verified suppliers but from China or from Europe ? Thats a different story or ?
Here probably is the same, I have heard they start fighting very hard against fake products, so with a chinese advice I would easly be able to find verified cells even if it is chinese brand it doesnt mean it is bad quality.
I find hard to believe that from a place where the battery market is growing so fast that here doesn’t exist good quality national brands.
I am in China working for a long time, when I order they normally think I am a chinese guy. Maybe you don’t know but before I came to China I never imagine how this was here. Everyone has an electric scooter here, in 100 scooters only 1 is gasoline. Very hard to find, so I think the batteries are all improving very quick here because people need the range to go to work etc.
Most electric scooters here can do around 30km or probably more and the range is at least 30km and the batteries don’t look so big
Got a set of lg hg2 from litto kalla a time ago.
Checked capacity and they like rated 3ah.
BUT they all have the same serial numbers…
So who knows what cells I got and which discharge rate they can handle.
I don’t use them for my eboard for sure.
A good reputation and rating not always a good indicator. Most people use the cells only for easy low drain applications and they test only the capacity by a charger.
There are only a few chinese cells tested on Lygte.
These 21700 are tested as well as the 26650 Littokala’s I got.
https://lygte-info.dk/review/batteries2012/LiitoKala%2021700%204000mAh%20Lii-40A%20(Yellow)%20UK.html
These cells won’t have a problem with 15A continues discharge so max 20A peak is perfect for these cells.
I compared it with the sanyo 21700 cell so you guys can see the small difference in performance at 15A.
I know everybody want to stay away from them but I’ve tested the capacity to be sure that’s right and I got 5016mAh from my 26650 littokala so that seems te be right.
Charge cycles. Build quality. Consistency cell to cell and batch to batch. Safety mechanisms. Temperature tolerance hot and cold. Overcharge/overdischarge tolerance. Random cells can be great or horrible at all these things. Brand names tend to be very consistent.
!
anyone knows these ones? Converting the price is around 2.2€
These cells won’t have a problem with 15A continues discharge so max 20A peak is perfect for these cells.
I compared it with the sanyo 21700 cell so you guys can see the small difference in performance at 15A.
