1 More Battery Question Increasing Amp Draw Battery C Rate

[joby1]

Hi, first off this forum is great, thanks everyone for sharing your info and thoughts!

I have Cyclone 1800-3000w motor, with stock 40amp controller.

My current battery is a calibike 48v 20ah 18650 cell based pack rated for 40 amps continuous. It is not made up of PREMIUM high C rate cells, this I know.

I have put a couple hundred miles on the system and have not detected any problems with my riding habits in relation to the motor or battery, aside from a little warmth of motor and battery, and a small voltage drop/lag at times depending on what I am doing. Overall I "think" the battery is performing well, all things considered..

I am planning on getting another battery and think that I have decided for now to get another 48v 20ah battery and run it parallel to the one I have now to extend range and ease the work of all the cells combined in the 2 packs.

The question is this, If I get comparable battery to the one I have now, rated at 40 amp draw, would it be possible to upgrade to the programmable 60amp cyclone controller considering the additional pack volume, total would be 40ah 48v pack. Would the additional cells allow me to get more amps out of the batteries safely, even though they are rated for 40amps continous each, or is that set in stone as a limit due to my current batteries rating?

Sorry for my ignorance, this is all new to me. Or if not possible to get full 60, maybe program it to 50 amps, either through controller or addition of a cycle analyst?

In the future I probably will get higher volt battery and transfer the one(s) I have currently to another bike or something, but for now I plan to just get another 48v, but more amps wont hurt for now, if the batteries can handle it...

thanks again for all your guys' help with the newb questions....

Joby

 

[Voltron]

Yes.. paralleling two identical ones will effectively cut the c rate in half, allowing a higher amp draw from the controller. You might have to up the size of the wires running to the controller and motor..

 

[dogman dan]

Agree. Though I do think you should limit to about 60 amps, because you will get a better lifespan, and less sag under load if your controller is set to less than your new max of 80 amps.

It's a lot of battery though, so think about how it will affect the handling of the bike. It can't all go in the triangle of a bike. 30 pounds will feel a lot different than 15.

I don't know how you carry your existing battery, but maybe just 10 ah more would be good if you have to carry it someplace less optimal. 8 pounds or so is easy to live with on a rear rack, handlebar mount, etc.

No issues with paralleling a 20 ah and a 10 ah. Voltage needs to match, not capacity. Personally I tote around 33 ah.

 

[pwd]

...
No issues with paralleling a 20 ah and a 10 ah. Voltage needs to match, not capacity.

Hey dogman,

can you explain that? That doesn't seem right to me.

 

[joby1]

Agree. Though I do think you should limit to about 60 amps, because you will get a better lifespan, and less sag under load if your controller is set to less than your new max of 80 amps.

It's a lot of battery though, so think about how it will affect the handling of the bike. It can't all go in the triangle of a bike. 30 pounds will feel a lot different than 15.

I don't know how you carry your existing battery, but maybe just 10 ah more would be good if you have to carry it someplace less optimal. 8 pounds or so is easy to live with on a rear rack, handlebar mount, etc.

No issues with paralleling a 20 ah and a 10 ah. Voltage needs to match, not capacity. Personally I tote around 33 ah.

Hey first off thanks everyone for replying...as usual thins places delivers the info !

Dan. first of all why dogman? just curious

my user name on a few things was jobydogman for a while...I bred dogs and trained for 20+ years, mostly working type dogs, sport work, OB, bite work and police k9... mollossers, bull breeds and herders most of the time...

I am going to put the next battery along side the first in the triangle bag, you responded on another post I had about it. You gave me 6 inch rule... should be fine my beast is heavy as hell already and has fat tires... it will stick out about 2.5 inches on either side of tube...and I dont peddle much at all...lol

60 amps will be the top for this setup for sure, maybe if and when I upgrade to the 7500w cyclone Id do more...

I dont have aspirations to do tons of trail riding, or tricks...mostly all road driving and some easy bike trails...

thanks everyone for all the help on here...loving my ebike so far..
Joby

 

[dogman dan]

Dogman because I think more like a dog than a man. I'm fluent in dog, and a low level dog whisperer. I don't dog train to verbal commands, I just communicate in dog they do what I want. Always lots of big dogs around. About the time I joined ES, I was cycling rescued bloodhouds through the house, finding forever homes for most of them. Getting stuck with the biters till I had quite a pack of crazy hounds that would attack.

Calmer times now, finally outlived those bad dogs, and have two rescued St Bernards that are pretty much sweet, except for the usual reason they get dumped, other dog aggressive. No more man biters.

My real nickname, is Danger Dan. That got started about the time I was 4 or 5, when I got caught about 100 feet up a pine tree by mom. I don't have to tell anybody my nickname, it gets pasted back on soon as people get to know me. I'm a classic adrenaline junkie.

Back to battery discussion,, you don't have to match paralleled batteries in size. If you connect a 20 ah to a 10 ah, what happens is 2/3 of the load is carried by the 20 ah, and 1/3 the load is carried by the 10 ah. They both will hit empty at about the same time. 30 ah is the total capacity.

If you series connect a 20 ah and a 10 ah, then the 10 ah will empty first, 10 ah is the total capacity. You do have to match series connected batteries pretty close.