Which battery pack would work for me?

JiggityJoe

10 mW
Joined
Jul 4, 2015
Messages
31
Location
New Britain, CT. USA
Hey, everybody ....new to the e-bike world, but man I wanna run and dive right in head first, after reading about mid-drive motors recently, especially the Big Block 3000w...I'm just a normal average mountain biker, never rode an electric bike, didn't even really know much about them or the conversion kit capabilities till I just happen to come across a link and then a video on youtube... looked insane, speed acceleration power an all that was great, on the flats, in the trails... although I'm more interested in the other type of "hauling", as in cargo...probably a seat mounted pull behind...maybe one of those tow-behind-bike-arm things...cut and modified and weld on a rack and wheel(s)...I'm a carpenter and need to haul my tools and supplies around... up an down some hilly loose dirt roads in Vermont... sometimes mud, snow, New Yorkers... so I want the torque and hill climbing ability more so than speed...maybe when I drop my gear, and grow a pair, I might get the need for speed... anyway, I have an older 2004 Cannondale Jekyll 600 FS I wanna try it out on, has a thicker frame or bottom bracket or whatever ( sorry for my lack of proper terminology and/or usage... past, present and future), but from what I read I guess he has mounts to accommodate pretty much every size, so I'm hoping my bike applies... I've done some research lately and have solved lots of answers to a lot of my own questions, and plan on putting more work in of course and learning everything I can. I only say that, because I don't want all you, way more highly intelligent people in this subject matter then me, to think I'm one of those lazy forum trolls who try to use people for their personal google or asked questions that have already been asked or can be easily answered with a little research... I have at least tried and figured some out, some I'm working on, but this one seems to be one for professional advice... and with that said, I hope I don't stick my foot in my own mouth, after asking this... What BATTERY do I need? lol...I know its not that simple... but that's the one thing I cant seem to find a solid "this is the one you need" answer on.... this is my first time actually asking, because from doing quite a bit of research on the particular battery pack system I would need for the specific tasks I'd like to accomplish with this motor and my bike, I can't find anything to lead me to the perfect battery...I'm still a newbie to all this, so I'm pretty sure I don't know what the full "item" list and/or specs of other parts I will (or hope to) use to fully lead me to the, all mighty battery would be... I just sent an email yesterday to the builder of this drive in regards to purchasing one, haven't asked him this question yet, but found and registered to E-S and saw he had a forum on here, so I figured I could get a few different and hopefully educated opinions from some of you in here that are users, of his drives, that is... so before I go through what information I used to conduct my research into the battery search, I like to hear from you guys and think it might be easier if anyone knows what specific information (or at least what you think would be best to come to a conclusion) of all other parts, products, my usage, average terrain, speed, conditions, etc., whatever, I would actual need to end this battery quest...I'm sure once we start discussing the drive package I'm going to buy, he will be able to answer all my questions, but it would be nice to learn from all of you riders in here as well... So if anyone is still reading this and has any input, please feel free... Thanks for your time Happy 4th and enjoy your summer riding season.... Joe
 
Welcome Joe. Batteries can be the most expensive part of an E-bike build, so there's no need to pay more for features you won't use, and that way you can get more of what you need.

Both the Lightning Rods kits (small block and big block) are designed to run well at around 50V. That being said, they will also run well at anything from 50V up to 72V. Above 72V the main problem is that high speed E-bikes should have a rear suspension, and that often means putting a shock absorber inside the frame triangle, which really limits how much room a frame has to mount a battery.

If you decide to use 50V, the next questions are, how many amps do you want (up to the amount of amps the motor/controller can survive), and how much range do you want.

If your max amps are relatively low, you can specify a less-expensive cell. more amps means more power for accelerating, but it also means more heat. The small block seems to be working well with 40A temporary peak, and 30A continuous (if you keep shifting to allow the motor to stray in an efficient RPM range, no bogging down). The big block might do twice that in amps.

The Amp-hours (Ah) of a pack is a relative way to tell how much range it has. More Ah means the pack will have more cells in it and will be physically larger. I recommend a pack made from 18650-format cells from em3ev.com, using the least expensive cell choice he has that will provide enough amps to meet your goals. A large pack can use the less expensive 22P cell, or the "long range" 29E...and still provide high amps. If you want a pack that is physically a little smaller (to make it easier to fit), The high-current 25R cell is capped by him with a 40A BMS, but...a 25R cell (even in his smallest pack) can provide 40A continuous.
 
http://endless-sphere.com/forums/viewtopic.php?f=3&t=70169&p=1058597#p1058597
 
Hey spinningmagnets thank you, and thank you for the reply as well...before I comment on the topic, I have to say, I noticed it says you're from Ft. Riley...in the military I assume?, if so, how long, what do/did you do?... just curious....I was stationed there back in 96...I was a dumb grunt 11M mechanized infantry...anywho again thanks for the response and for moving my question to a more proper category... I saw it earlier and what like what the F, where'd it go lol...I only posted it there because I was over-whelmed with all the other discussion topics and didn't know where I should post it...and then saw Lightningrod and him talking about his mid-drive, the motor I want to get, so figured I could jump right in and tag along with the rest of the Lightningrodders and see what battery choices they were using with this motor...Ok now the topic at hand...yeah I've seen most set-ups ranging from the 48v - and up to 72v choice of battery for the bigger watt motors.... the bike I want to fit it with is a full-suspension type and the rear suspension doesn't take up too much room, would have to mount battery pack up closer to the front of the frame, but still doable and think it could still accommodate a larger pack if I needed... for the controller I guess I will be going with the 12FET (40A) or the 18FET (60A) if I have to... having range would come in very handy at times, but for most of the times I will only be using the bike a few miles a day, and in some cases only using it every few days... so I'd liked to find something that has enough juice to power me up the hills (mostly just one way) with a heavy cargo load...and to push me through the off-road trails w/my cargo... and one that can hold a charge for a while if I happen to not used it for a few days...I would also like to be able to charge the battery with a solar power generator if possible... a battery that can keep me off-grid if needed, be easily charged by solar, hold said charge, be powerful and durable enough to last and get me up hills and through the woods rain or shine mud or snow, have the capability to give me long range when I need it, and maybe a little speed when I'm light and want to have some fun... Yeah I saw the "long range" 29E from em3ev.com making the 50v battery with 24.8Ah @ 1250Wh...good for range, but does it still mean I can use it for maybe shorter increments (low X miles/day) over a longer period of time (weeks or even months) and still give me the total 1250Wh of usage (minus the normal power drainage when not in use) before its needs to be charged again...and I'm not too concerned with the weight of the battery (or so I think) with all the gear hopefully a little extra weight in the battery won't be too much more to handle...I'd sacrifice the added weight for a good strong long-lasting battery if it would give me the hill-climbing ability I want and to pull heavy loads and with the minimal mileage, keep me from having to recharge for awhile... I'm not an electrician, but what are your thought on a LiPo battery pack connected in either series or parallel or even taking apart a bunch of laptop batteries and making your own DIY ...or is that just way too much work and too dangerous if you don't know what your doing...I'm thinking they are harder to maintain, charge, test, balance, etc., seems like an initial cheap way to go with a good battery though, but will probably prove to be more expensive in the end... just curious, but I think I will be purchasing a professionally made ready-to-go battery or 2 anyway...how long (roughly) could a typical battery, say the 29E or any similar 50v 24Ah, last...with light mileage usage but with some stressful towing uphill, over the years and proper maintenance?.... and I still (for now) plan on producing my own power and pedal as much as I can when I can, to hopefully help me make the battery last (in years) as long as I can...and maybe even rig my portable solar panel to mount on bike and soak up some sun power on the go when I can. And as far as the amount of weight I'd like to haul, what comes into play to allow me to carry 200lbs (I could dial it down) or at times more (if possible)...motor, battery, bike,...everything?...the Big Block seems to sounds like it can do the job...how much do you think it can pull? guesstimate... flat ground vs uphill vs some rough off-roading...with vs without gear... and so, the battery pack that would be able to handle the 3000w motor (with the proper controller) and assist me in hauling (X amount lbs) gear uphill and/or off-road trails in the snow for a few miles not to be used for, lets say, a week...and then travel my route again and as many times as possible before having to recharge...would be....?... I'm just picky and want the perfect battery and not schooled in this subject enough to risk a bad expensive decision and don't want to wait any longer to figure it out because I want to try this electric drive so bad right now lol, so I need to reach out to you experts who have been there, done that to help a newbie out...I made plenty of my own mistakes before and learned from them, that's the fun part of self-education...living and learning, trial and error... but money is a little tight, and like you said, the battery can be the most expensive part of the system...I don't mind shelling out some bucks on a great battery the first time around.... I just don't want to screw that part up and hurt myself financially and force myself to find somewhere else to make up for the error... and then in the end basically have an overall poor final product that may not give me the results I want...so if anyone wants to have leniency on me and spare me the burden of suffering your past mistakes and give me your wisdom or anymore advice to what you may think the "perfect" battery would be for me and my usage needs...would again be greatly appreciated... thank you spinningmagnets, I learned a few things from your post, one being, that I didn't know about the capping of a BMS...this may be good if I need a smaller/lighter pack with high amps...if its strong enough to help handle the tasks I'd like to accomplish... I'd rather have more then I need (within whatever safety precautions and the limits of all the other components/pieces to the system that apply) and be there when I do need it, then to not have it when I need it...so again, if anyone else has any more suggestions to go along with the above mentioned, as to the best battery pack system they'd recommend... please share....thank you....Joe
 
Hey, Spinningmagnets, again thanks for your input...don't waste your time reading my last post if you haven't already lol...sorry if you did, I tend to ramble as thoughts come to my head and type away... Anyway, I think I found the battery...or at least the type, after hearing about it from you, and Mike, the builder of the beast, and seeing it before and looking more into it now, I'm going to go with a 25R model.

Not sure of the volts and amp hours yet...probably the 52v 20Ah one if I do some measuring and see if it'll fit esthetically ... might be a little big to fit comfortably in triangle but I'm sure I can come up with something if I go with this size...other choice would be the 25R ; 52v 12.5Ah one in the triangle configuration already, would fit perfectly of course...just not sure if that is enough Ah for the Wh's I'd like to get out of a battery.

But I think I'm starting to confuse myself...so many numbers and letters it's all starting to jumble lol...Well at least I am sold on the 25R's though...not sure what I want to sacrifice yet, but I am narrowing it down thanks to you guys... maybe I'll just buy one of each, that will solve it I guess, right.

Joe
 
Good, it sounds like you have narrowed it down a bit, and that will help you when shopping. When there are too many options, it can get confusing.

I work at Ft Riley right now. I was in the Navy from 1977-81 in San Diego.
 
yeah its gonna be one of those two...the smaller one that will fit or the bigger one that I want, and somehow make it fit.

but yes for a green newbie like me, all these choices with all the pros and cons, can get really frustrating...I knew it wouldn't be easy, but I think I might be in over my head here ...takes a lot more knowledge in a few different fields to pull this off...its a lot more then just slapping an electric motor on your bike and riding of into the sun set lol.

oh ok cool...I was in D 1/16 right out of basic, from 1996-99 before I got deployed to Germany.
 
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