kracksmith

my stock 8ah battery using 21700 cells isn't cutting it with capacity riding in a ebike group ride. most has surons and they got minimum 20ah and most has high 30's ah. I need at least 20ah.

I'm deciding on either one of the 2 below. both are 50amp continuous which my controller needs and both are 52v 21ah (i'm sticking to only 52v for now). but one of them uses 3500 cells and the other one is 18650 cells. They both cost the same but which cells are more ideal over the other?

https://www.electrifybike.com/collec...bike-battery-1
https://lunacycle.com/52v-luna-direwolf-ebike-battery/

2old

They're both 18650 cells (from being 18 mm in diameter and 65 mm length). AFAIK, Luna has been out of stock on most batteries forever.

kracksmith

ok thanks so they are both the same. I'll order it from the 1st link then.are there any company that does 52v 40ah? I checked with Amazon, they have 52v 30ah but they said their battery can't accept the 50amp continuous which my controller requires.

2old

Lithium Battery Universe for one; just put the requirements in your browser. Disclaimer: I haven't used this company. If I were looking for a battery that size I'd probably see if em3ev would construct it.

chas58

There is a lot of batteries other than just the size. There is a big difference between cheap and expensive batteries.

One of the most important aspects is C rate. Roughly if you have a 10v battery, and it can do 10 amps it’s a 1C if a 10V battery (pack) can do 50amps, it’s a 5 C battery.

Big difference in performance and life span if you are pushing the batteries any where near the limit. You probably want a capacity twice what you need – as getting near capacity is going to shorten its life, cause performance issues, and generate heat (bad).

I tend to do the research and get a high capacity Panasonic or Samsung battery. I need the high capacity, because I tend to use small battery packs, and need the higher C rate. Luna (last time I looked) tends to use pretty good batteries.

Doc_Wui

They are both 18650 cells in a 14x6 matrix for 84 cells. The cells are the same capacity, 3500 mah in both cases. Luna tells you that they use LG MJ1 cells, while the other guy offers Panasonic 35E or Samsung GA.

Of these three types, I would rank the GA and MJ1 first, as they are rated for 10A discharge, while the 35E's are rated at 8A. With 6P, theoretical max currents would be 60A for the first two, and 48A for the 35E. In practice, your controller determines what you will pull, but the MJ1 and GA will have an easier life and last longer if you don't get close to their max ratings,

Anyway, you cannot get a Luna pack,

kracksmith

EM3ev 52V doesn't have a 21ah and only shows a 17ah.

I think it's best I go with electrifybike.com 52v 50-amp 21ah Mega Shark E-bike Battery. It does 50amp continous as what my controller can max out plus it's 21ah. This company is reputable to use good battery (requesting Panasonic GA cells).

I also bought the electrifybike 52 80%-90%-100% battery charger where as I would charge only to 80% unless I go on a group ride. I do try to not go under 20% rule too. So for causal riding around I only use 60% of the battery using from 80% to 20%.


Thanks for the feedback to allow me to make the right choice.

2old

Please keep us informed on the performance of your battery; some of us will need another one some day. Also, check when you charge to 100% (which they may tell you to do from time to time to balance the cells); should be 58.8V. Thanks.

EridianTech

u can use old laptop cells. most laptops has LG or SAMSUNG cells. sometimes workstation class one has Panasonic cells, i got this working in my bike,

KPREN

Been looking at this for better than a week but have not answered this post. To many bells and whistles going off about inconsistencies. I got hammered as mean by the last newbie I tried to help. He wanted confirmation instead of knowledge.
You want to ride with Sir Ron bikes you buds have, a ligit 40 mph, 2,500 watt light electric dirt bike. You have an 8 amp Hour battery with 21700 cells. No doubt PF technology. You have a 2,600 watt bike (52 V times 50 amps). Yes, even with PF technology you are going to sag that battery very fast and it will cut out trying to pull 50 amps and the battery will be very short lived.
You are looking at larger batteries with GA and E technology as replacements. GA and E technology will not put out the amps that PF technology will and those batteries will not sustain you any better. Think 20+ amp hour at least with PF technology and go play short hops with your bud on the OVR trails. Enjoy the battery while it lasts, high power and speed comes at a price. A real dirt bike is a hell of a lot cheaper overall.

kracksmith

You may not know it but I do appreciate your replies as always, every bit helps and I will absorb it and just make a decision at the end whether it's a bad one or could be a good one.

I do understand I would never keep up with a emoto by having a ebike. They will beat me in any which way I build my ebike. I still don't know the durability of my build yet as the most I ever went was just 20 miles on a group ride. In this 20miles I actually did well, with PAS and riding with a slower crowd, I still had 80% at the 10miles mark. There was a charging station so I only used 20% back as well, this is with my lousy 8ah. With the new 21ah plus 8ah, i'm estimating 50 miles with no PAS, with PAS much more. Riding with sur ron guys their capacity is 30-40ah and at 72v, so not expecting to keep up, but distance wise i should be able to get to those same places at a slower ride.

KPREN

I am speaking from experience. I have the bike you want. It's a titanium fat bike with a 52 volt 49 ah battery (1080 watt nominal motor). I can sustain 28 mph with the bike on fairly level roads. Throw in a longer climb of 6% and I will overheat and fry the motor in about 8-10 minutes. I can sustain 20 mph with short grades up to about 10-12% with a light load. I would suggest that you go play with Grin's simulator to get a much better grip on reality. Motor Simulator - Tools (ebikes.ca) Their simulator is surprisingly accurate.
My experience: I have a $6,500 do it yourself e bike that screams badass. Whenever these total asshats want to insist that I am on a motorcycle I just want to throw them into the nearest dumpster because this bike, for all its capabilities, frustratingly is still a GD bicycle with all the faults of a GD bicycle meant to ride no more than 18-22 mph on pavement and gravel roads. I am much more tense at 28 mph and very tense at 35 mph. My bike is not a road bike, it's a rough off-road bike with deafening tire noise above 20 mph on pavement.
I can pull about 75-80% from the capacity from my batteries, not 90%, due to sag and age, around 2,000Whr. At 28 mph on good roads and fairly level, my mileage is around 37Whr per mile. At 22 mph my mileage is about 27Whr per mile. At 20mph my mileage is about 22Whr per mile. At 18 mph my mileage is about 17Whr per mile. The best I do with this bike is around 12-13mph at 11Whr per mile. The worst mileage is heavy snow at 5 mph with 3 psi tire pressure ~ 55Whr per mile. It's capable, so it's a heavy bike with high windage and high rolling resistance tires. My mileage at heavy touring load is about 5Whr pr mile worse.
Those are the numbers I live with every day. I can improve on them about 5Whr per mile with narrower 2.5" low rolling resistance tires, instead of 4.8" width heavy high rolling resistance tires. I currently am running Maxxis Minion 4.8" tires, essentially a 31" tall dump truck tire.
I pedal all the time, can't stand using throttle. You are quoting me numbers that are consistent with lower speeds under 20 mph average to get the mileage you stated above with your 8ahr battery. Do you really need 30 mph. The cheapest way to get that is a Sir Ron dirtbike.

kracksmith

Thanks very much for sharing your stats. They are very interesting to know, this allows me to want to attempt the same as I'm curious what my build is giving me too. You look to have a nice setup, do you have any pictures you can share? or do you have a build link?

I don't want to spend too much but yes anything Ebiking is expensive, especially going the Emoto route. My bicycle was 700 new in 2008, the motor/battery is 1550, now this new battery is 800, so I'm in a bit over 3000 so far. Reading your killer build stats, I now realize i can't keep up with Emoto with their speed runs for 20-30 miles going 30-40mph due to my ebike battery capacity limitation. I probably just can do a easy group ride going 20mph and not even attempt racing as itll just drain my batteries and I'll lose capacity for distance. My ebike will be used as a bicycle so mainly PAS and just regular pedaling but seldom times just throttle for fun.

It just looks fun riding in a emoto group ride but it's costly, their price tag is 10K for their build. If I have to go long distance I should just buy a Yamaha R3, but this platform won't allow me to ride in bike paths, through parks, and sidewalks. Pros and cons like everything else in life.

Today I wanted to test zipping around, I basically just full throttle throughout my neighborhood, was fun and hit top speed of 47.5mph today. I rode only 5 minutes something and it used up 60% of my 8ah. 80% to 20%. I had on a real helmet.

KPREN

Here are a few uploaded photos

touring mode

Battery attachment front forks

Bike with riding partner

Winter mode
Full studded 4.6" tires

kracksmith

Super nice choice to pick a titanium frame for your build, it's light and strong made to hold up well over time. Just a few questions

• Approximately how much does it weight with just motor and battery
• Where did you get your 52v 49ah battery, largest capacity i could fine was a 21ah
• What kind of motor, looks nicely sealed too

Ebike/Emoto both are just too expensive to get speed and distance right now and the limitation is mainly the cost of the battery. For now I won't even consider purchasing an emoto such as a Onxy or Sur ron due to their overall cost, as battery has a life of 800-1000 recharge cycle from empty to full then needs to be replaced. Good Emoto batteries are very expensive too, 2500. I maybe entertain with a Super73 though someday. I would say the same for a Telsa. Tesla owners will face the same thing after 8-10 years where they will need to make a decision to either buy new batteries or just get another Tesla and make payments all over again. Hybrid cars could be more ideal if they make them go faster and design better. Replacing a smaller battery on this wouldn't cost a fortune.

I still think I made a right choice of building a Ebike just for the loving sake of putting a kit in a bicycle. So for now I will continue to ride and enjoy my ebike as a pedaling bicycle and use PAS and throttle when needed.

Thanks for sharing your awesome pictures, looks fun and adventurous out there.

kracksmith

I'm kind of curious will any of these 52V work on a 48V controller such as a Super73 zx? I'm thinking to buy a super73zx for my family to ride together and use this 52v on it for longer rides myself when i borrow it?

I read several links yes, then i read other links it says no but in a technical aspect, is it ok or will it damage the 48v controller?

2old

Usually (maybe always), 48 V controllers have capacitors for 60V or 64V (can't remember) so are safe for 14s (52V) which charges to 58.8V. However, getting a battery that can interface with the Super 73's controller may not be easy (I don't know what their system looks like), and (probably) will increase top speed by a couple of mph, but not add that much range unless the batter has a higher capacity. If I were you, I'd just procure a second "73" battery (then, again, I'd get an ONYX CTY). Disclaimer: The ONYX is illegal to ride as a "bicycle.

kracksmith

I may just get a 2nd hand good used Super73 zx as I do like the style and has good platform to add bigger capacity batteries. I will get rid of the 48v stock motor and controller to upgrade it to a 72v 3000/5000 watts motor instead, anything below 72v these days isn't cutting it for power. Yes no suspension as I want to keep this as light as possible. Will use it as a cruiser like my current ebike but once in awhile race straights for top end.

Well I just came back from a 25miles group bike ride and last 1.8 miles i had zero battery left so had to pedal 47lbs of the bike. Yes not good to drain to zero. My 8ah could of made it all 25miles if i would of rode granny style and not raced one bit. I think I only raced maybe 3-4 times going top speed then when going home had serious battery and distance anxiety. No wonder most ebikes there was just on cruising mode but the Onxy guys was just speeding all the time. I talked to some of them and their upgraded battery was 5K alone. Some of their Onxy was 13K in total. It was fun and great group of ppl to ride with, all had ebike/emoto passions. Oh I did fast charge halfway point too but just 45mins.

I really need a bigger capacity battery which I haven't bout yet waiting for Luna version.

2old

Luna has been out of batteries (except for SurRon and one or two of their bikes seemingly forever (probably at least several months). Very strange, especially since they had problems with at least one "Wolf" battery and needed to send a kit to protect it from some environmental problem.

KPREN

My apologies, I know that I typed a response to this post, but I don't see it here so I will type one again.
With just the motor and batteries the bike weighs 75 lbs
The 49 amp hour battery is actually 4 batteries in parallel. The four batteries act as one huge battery and I charge them all at once. They basically have the same voltage all the time. Each battery has its own BMS and I generally charge through each BMS. I have a harness with four bayonet plugs on it and plug in each battery. I have fuse links to all batteries. I cannot accidently plug in one battery to the full 15 amp charger or the fuse will blow. The fuses are 7.5 amp. I have to plug all the batteries in before connecting the charger. I have accidently had the charger on and started to plug in batteries. After the second I realized what I was doing and sure enough both fuses were blown.
The motor is a standard Bafang BBSHD 120mm wide bottom bracket. I made custom fairings around it to protect it from spray and crud from the tires. I also have fairings behind the batteries to protect them from water intrusion.
Most of my riding is done below 20 mph. The last ride out I averaged 12.7. The bike will maintain 20 mph if I want it to, even on moderate grades. I can even maintain 25 with slight hills. Maintaining 28 mph is stressful to the system and has a danger of overheating in warm weather.
Maximum motor output under the right conditions is just under 1,100 watts. You have to have the right conditions to exceed 750 watts. As an example of what I mean:
Maximum power draw that I have seen from the batteries is 1,700 watts. To get 1,100 watts motor output requires that the motor be at max rpm (Cadence of 130 rpm) and max load (any more load will slow the rpm down) It's pretty hard to add any of your own power at 130 rpm so you are full throttle to get that motor output.
I have seen 1,700 watts battery draw at a speed of about 6mph climbing a sand dune at maximum stacking angle. Motor output was about 550 watts @ 170NM of torque.
All perfectly legal as the regs are written as motor output and not battery draw. Yes, you can be showing 1,700 watts on your meter and only be at 550 watts of motor output. That translates to an efficiency of just over 32%. The rest (67+) percent is quickly heating up your motor core and wiring and, is not sustainable for more than a few minutes.

kracksmith

very interesting data you got yours down to a science i do like how you got your battery setup like that

yes Luna battery been out i might just go with the other one since it says 50amp continuous which i require.

pierce

a 52V 50AH battery is like 2600 watt*hours, thats massively huge and heavy.

if your motor is overheating, get into the controller settings menu, and limit the maximum power to like half what the motors rating is, and plan on a little more pedalling and less pure throttle.

me, I'm using a mid drive Shimano now... at its highest pedal assist setting it can still go 60 miles on a 500WH battery, thats 1/4 the size of what you were talking about, but because its pedal assist, you will be pedaling the whole time.

if you're riding with a group thats going too far and too fast for you, find another group. more you ride at a comfortable pace, the stronger you will get and the better your endurance will be. use your gearing so your pedaling is smooth and at a reasonable cadence, at least 60 full pedal turns per minute, and that will build your endurance.