Im am building a battery for the cyclone 3000 kit. I originally was building a 15s15p configuration but now think maybe i should build it bigger. Looking at 18s15p possibly. Will i miss out in much power with a 15p vs 18p setup? That would work out to 54volts vs 65 volts nominal.
-
-
The high voltage will give more RPM so more top speed. It depends on what you want. 20s10p would be the ideal Cyclone battery. -
Is there any concerns with having an initial max voltage of 82 or 84 volts when a 20s battery is fresh off a charger?Comment
-
When you go higher voltage there is always a concern. More voltage more amps = more heat.Comment
-
I think this would be a relevant thread so I don't spawn a new topic.
I just got 80x 20700 Cells and I'm thinking about doing a 20s4p (17Ah 60A) Ńonfiguration for Cyclone 3kW. Apart of small range, what else may be the problems with such battery setup?Comment
-
Do you know the C rating of the cells? What is the chemistry (e.g. LiMn) of the cells?
The rule of thumb is to multiply the capacity of the battery (in Ah) by the C rating of the individual cells to get continuous current (in A).
In my case, I have a 19.8Ah battery with cells that have an advertised C rating of 3, so I can draw 19.8 X 3 = 59.4A continuous (in theory).
After testing two systems with this same battery for many miles, I saw that I could only draw 30A continuous (in practice). So it would seem that the vendor exaggerated the C rating. Note that the vendor was NOT Luna.Last edited by commuter ebikes; 01-05-2018, 08:07 AM. -
The cells Are Sanyo NCR 20700B, So chemistry should be Ni-Co, they're rated 15A, 4050-4250 mAh. I didn't find the C rate mentioned anywhere (if I calculate it from the Info I have I get ~3.7 C, but I guess it should be calculated not with the max continuous Amp rate.
UPD: ordered extra batteries to make it a 20s5p
-
-
Actually incorrect.Originally posted by Rodney64 View Post
More voltage at SAME amps, more power (Watts). Which, yes, can potentially end up as more heat. Generally though if you want more power, you can do 1 of 3 things. Increase voltage, increase amps, or increase both. If you increase amps you WILL get more heat, which might mean you need larger wires and higher capacity connectors. If you increase the voltage, you may not get much more heat or need to change out your connectors. As long as the voltage and amps remain within the rated spec of the wiring & connectors.
Although frankly I'd prefer never to run anything right at it's rated spec, and even in bursts stay below the rated spec.
So personally for batteries, once you get to controller/wiring that can handle 30a, I'd personally prefer to go for 20-25a at higher voltage. If you've got something like the Cyclone, well, both. Although according to https://lunacycle.com/cyclone-mid-dr...planetary-kit/ it's max is 72v I'd treat that as the maximum, so I'd stick to that as your max nominal voltage, not the 82v or 84v mentioned above unless that was mentioned as a max voltage (fully charge). Remember you'll also get a voltage dip as power is pulled.
What that means is then increasing the amps, which yes will definitely end up with more heat from the wiring. The kit controller can handle up to 40a, so I'd ensure the battery can handle that, as commuter ebikes said above, you need to look at the C rating of the cells, the Ah of each cell, and then multiply that by the number in parallel. So for 20s that'll give you the ~72v nominal, if they are 3200 mAh 3C rated cells that's 3.2Ah * 3, 9.6 A continuous load. I wouldn't want to run it at that for very long, it'll also put out fair amount of heat, but you could in theory. If you're running 20s5p, that means 5 cells in parallel, which at 3c 3.2Ah would be theoretically at 48A continuous load. Acceptable for that 40a controller, but personally I'd look for 4c or 5c cells, or go more than 5p.
Schmeisser, according to https://www.amazon.com/Panasonic-NCR.../dp/B07918BYMX it's 10A continuous, so looks like it's probably 15a peak. So probably a 2.5-3C rating. I'd say good thing you went for 5p, that'll be safer if you live towards the higher end of the power. If you tend to be more 1000-1500W you'll be WELL under the rating.Comment
Comment