range?? 48v 15amp or 36v 15amp
- Thread starter kriskros
- Start date
biohazardman
100 kW
Difference will be in the size of the EV grin. ;^) 36V small one 48V bigger. 48 volts will accelerate more quickly, climb hills better and have a slightly higher top end. You should get near the same range but I got near a mile less on 48V cuz I went a bit faster all the time. You want the 48 and once there more. ;^)
BikeFanatic
1 kW
I second that, 48 is better , you should be able to squeek out an extra mile or so, if you keep
the speed down.
the speed down.
dogman dan
1 PW
Count the pouches in a ping pack for the answer. 36v 15 ah has 3 x12 cells, 3p-12s. 36 pouches A 48v 15 ah is 3p 16s. 12 pouches more for a total 48 pouches. Obviously the 36 cell pack has less total capacity than a 48 cell pack.
For use with 20-25 amp controllers typical in motor kits, the 36v 20 ah and 48v 15 ah are the ideal sizes in pingbatteries. both the same number of pouches, they weigh about 15 pounds and typically can fit in many rear carrier bags or boxes, or toolboxes. The 36v 20 ah will theoretically last longer, since it can provide 20 amps at a lower c rate than a 15 ah battery. The 48v 20 ah size sounds good, but the extra 5 pounds seems to cross a threshold for carrying on a rear rack without making handling more difficult, and handy boxes or bags to carry it get harder to find.
In identical capacity batteries, the 36v version would have better range than the 48v if each was ridden full throttle. Both would theoretically have identical range if each was ridden the same speed. The lower c rate of the discharge on the 36v may give it a slight advantage, but I doubt it would ammount to much difference really. You oughta be buying enough battery to have a 20-30% reserve at the end of the typical ride anyway, just to be kind to the battery and have enough for those days when you have the pack a bit out of balance. So any small difference in range would be tiny compared to the reserve you should be designing into your battery.
Out on the road though, the 48v battery will have a definite advantage over the 36v when it's time to climb a hill, or go a bit faster to get across a busy street. If it's practical to on your route, the faster speed will get you there faster.
For use with 20-25 amp controllers typical in motor kits, the 36v 20 ah and 48v 15 ah are the ideal sizes in pingbatteries. both the same number of pouches, they weigh about 15 pounds and typically can fit in many rear carrier bags or boxes, or toolboxes. The 36v 20 ah will theoretically last longer, since it can provide 20 amps at a lower c rate than a 15 ah battery. The 48v 20 ah size sounds good, but the extra 5 pounds seems to cross a threshold for carrying on a rear rack without making handling more difficult, and handy boxes or bags to carry it get harder to find.
In identical capacity batteries, the 36v version would have better range than the 48v if each was ridden full throttle. Both would theoretically have identical range if each was ridden the same speed. The lower c rate of the discharge on the 36v may give it a slight advantage, but I doubt it would ammount to much difference really. You oughta be buying enough battery to have a 20-30% reserve at the end of the typical ride anyway, just to be kind to the battery and have enough for those days when you have the pack a bit out of balance. So any small difference in range would be tiny compared to the reserve you should be designing into your battery.
Out on the road though, the 48v battery will have a definite advantage over the 36v when it's time to climb a hill, or go a bit faster to get across a busy street. If it's practical to on your route, the faster speed will get you there faster.
TylerDurden
100 GW
The 48V pack has 33% more energy stored than the 36V, if the Ah are the same.kriskros said:
If you ride the same speed as the 36V, the 48V pack should provide about 33% more range.
If the motor is the same in either case, the 48V pack can provide about 33% more speed; but if used at that higher speed, you should get less range than the 36V pack, since increased drag requires much more than 33% more power.
dequinox
10 kW
Yeah it usually comes down to how much work the pack will do and how much work the pack has to do.
By Watts x Hours=Volts x Amps x Hours (P=VI);
36v*15A*1h=540 Watt-hours
48v*15A*1h=720 Watt-hours
So yes the 48v pack would, traveling in equal conditions as with the 36v pack, give you 25% more range. If you are throttle-happy though you'll possibly get less. I've come to believe based on my brushed setup, that there is a certain point where jamming the throttle down all the way draws more current but doesn't provide much more in the way of usable power. ...And by usable I mean electric power translated into mechanical power.
By Watts x Hours=Volts x Amps x Hours (P=VI);
36v*15A*1h=540 Watt-hours
48v*15A*1h=720 Watt-hours
So yes the 48v pack would, traveling in equal conditions as with the 36v pack, give you 25% more range. If you are throttle-happy though you'll possibly get less. I've come to believe based on my brushed setup, that there is a certain point where jamming the throttle down all the way draws more current but doesn't provide much more in the way of usable power. ...And by usable I mean electric power translated into mechanical power.
dogman dan
1 PW
I suppose it depends on how you look at the math, I come up 25% bigger. The way I look at it 3 cells plus one more cell is 25%. but it is 33% of the original 3 cells. Mabye what I really mean is that the 36 volt is 25% smaller than the 48v.
Just the kind of thing that shows how stuff like global warming or unemployment statistics can be massaged to say different things with the same data.
Just the kind of thing that shows how stuff like global warming or unemployment statistics can be massaged to say different things with the same data.
dequinox
10 kW
It does depend on how you look at it...and it can really be both in a certain sense. You can either go hey I've got this much now, and I had 75% of what I have now.... or you can say hey I have 3 cells, each one worth 33% of what I have, then adding another one means adding one more third to the setup. Its a 33% increase, and 25% greater capacity. Weird to think about huh?
DAND214
10 MW
After all of that BIG IS BETTER! I like it bigger much more fun.
Dan
Dan
dequinox said:
"36v*15A*1h=540 Watt-hours
48v*15A*1h=720 Watt-hours"
The above I agree with but I don't see where the 25% comes from as an increase.
If you are looking to find out how much further you could go if you stepped up from 36 to 48 of the same amp/hr (discounting weight and other factors) you'd take the difference of the two rating 720-540=180 and divide the difference by the 540 because you want to know how much further you can go then on 540 so 180/540=33%. If you knew you could go 15 miles on 36 you should be able to go 20 on 48.
If you are looking to find out how much distance you'd lose (discounting weight and other factors) you'd take the difference of the two ratings 720-540=180 and divide the difference by the 720 because you want to know how much less you can go then on 720 so 180/720 = 25%. So if you went 20 miles on 48 you should be able to go 15 on 36.
TIs like my 401k.. Lost 50% of my money and to get back to where I was I gotta gain 100%
It is all how you look at it but you gotta make sure you use the right comparison with the right text and not mix em up like my boss does constantly.Course all the calculations in the world ain't gonna help if you full throttle it all over the place and run headlong into a head wind burning up power much faster with the high voltage such as Dogman mentioned. I'm thinking about going with a higher voltage pack and then using a cycle analyst to keep it honest and the draw low.
