48V and 17.5ah GA for 80km range. Possible?

[sisachosudo]

Hello everybody.

First post but I read hundreds of them. Thank you for helping me to slowly climb the learning curve. Battery chemistry can be really confusing sometimes.

After an extensive research I am planning to buy my first battery and my first option is the Luna Cycle Jumbo Shark Panasonic 18650 GA 17.5ah - 48V

To narrow the search I used this parameters:

- Has to be a dolphin/shark fixed to the frame as it will be my first ebike and do not have the experience to buy the cells separately.
- Besides that, I will use it almost every day in short trips to the office. It is a flat 10km route each way.
- Totally safe and easy to use (no LiPos).
- Would it be too much to expect around 80km of range (flat route) at 32km/h (20 mph) with 50% assistance? During the summer I use my road bike and I would love if my wife can keep up with me using this kit, that’s why I need the battery to last at least 80km.



I considered other options like Em3ev but the dolphin packs they list on their website give no more than 680 watts per hour instead of the 840 wph coming out of the Luna Cycle pack.

Sorry to ask you this question but I cannot manage myself to understand and use properly the ebike.ca calculator. Do you think I can reach the requirements from the last point in the list above with this 17.5ah 48V Panasonic GA pack?
Can somebody clarify what would be the range and speed at full throttle?
I believe that the closest battery in the simulator is the one named "48V 20Ah AllCell".

I do not have the engine yet but most probably will be a Nine Continent 1000W rear hub motor.

Thank you very much for your help, it is really appreciated.

 

[Wheazel]

First calculate roughly how much energy you have in the considered pack.
In your case I would guess the pack can deliver around 700Wh with a small margin.

To ride 80km on 700Wh requires you to consume no more than 9Wh/km. Which is a quite low number.
However it is very possible if you pedal along and ride 30-35km/h max.
Can not do it without pedaling I think, unless the ride is very aerodynamic.

 

[DVDRW]

Speed determines range mostly.
If i ride 70km/h i get ~80km
If 25km/h then ~350km
Without pedaling
4 kWh triangle pack.

 

[Hillhater]

Using less than 10 Wh/km needs a lot of pedaling to achieve...and an efficient motor.
So unless your wife is very bike fit, the route is very flat , (and likely you ride slowly), it will be a stretch to make that 80 km without a lot of pedal input.

 

[sisachosudo]

Thank you all for your replies.

I read in the forum a general rule saying that you need 20Wh per mile. Following that, with the 840Wh battery I would end up with a range of 42 miles (67Km).

She is very light but I do not believe she will do a lot of pedalling.

Do you know another battery with more watts per hour to extend just a bit its range? It has to go in the bottle cage, like shark or dolphin batteries.

Thank you again.

 

[Wheazel]

Thank you all for your replies.

I read in the forum a general rule saying that you need 20Wh per mile. Following that, with the 840Wh battery I would end up with a range of 42 miles (67Km).

She is very light but I do not believe she will do a lot of pedalling.

Do you know another battery with more watts per hour to extend just a bit its range? It has to go in the bottle cage, like shark or dolphin batteries.

Thank you again.

It's tricky to find a specific tailored battery solution unless you make it yourself, or hire that service.
That said, I build my packs myself and have lacking knowledge on what packs you can buy.
I know forum members have offered, and might still be offering tailored solutions out of quality cells.

Have you calculated if your needs fit in the available volume? Its all about the number of cells times xWh (depending on cell and charge range) you need.

 

[Tats]

Would a triangle battery and frame bag work for you? Might open up more options.

 

[alfantastic]

If money isn't an issue, why not just buy two dolphin 17.5ah 48V Panasonic GA packs, then swap them over when one gets depleted.

You could either store the second one on a decent bike rack, or your wife could carry it in a backpack.

 

[999zip999]

It depends on riding style and Terrain. I think a lower watt demand motor would help. Plus what speed are you looking at ? 18mph to 22mph with peddling ? Just to keep up with you.

 

[sisachosudo]

Hi guys,

yes, the speed would be very close to 20mph and constant. Route during the long trips (where range could be a problem) is only asphalt and totally flat.

I thought about getting a triangle battery in a bag but I love how dolphin/shark look in the bike. Would not be a problem to cycle on a rainy day with the battery just protected by a bag made of fabric?

The idea propossed by alfantastic of getting a second battery and carry it in the rack is not a fool one neither, it will be considered if I do not find a better solution.

Now I am a bit confussed regarding Luna Cycle, I thought it was one of the best suppliers you can buy from if you are looking for original and good cells. I am located in Europe and I do not find it easy to spot a good supplier but so far Luna replied all my queries promptly.


Thank you.

 

[sisachosudo]

Thank you for naming EVMadrid, I will get in touch with them.

If GA is not a suitable cell for an ebike, which one would you choose? 30Q?

Thanks.

www.swimbikewrite.com

 

[Ykick]

So no photos of said inspections or links to actual threads or testing data? Blah, blah, blah like a self-appointed sheriff of “nothing-land”…

OP, it’s fairly obvious when someone’s working a vendetta as is the case here. Please do your own research and decide for yourself.

As far as advice? I dunno if buying a battery from Luna or any vendor outside your country is a good idea or not? That can get complicated in the event something is found defective? And defects can happen to ALL vendors.

I’d certainly ask any vendor “what if” there’s a problem?

But as far as Luna is concerned I’m a happy USA customer and have enjoyed prompt pre & post service inquiries. Much quicker responses and resolutions than many vendors I’ve dealt with over the 10 years I’ve assembled and used eBikes.

 

[Lurkin]

I've used an em3ev dolphin battery for commuting for almost two years now. I purchased a BBS01 kit, battery and charger. Plug and play, never had any battery issues. The kit was a different story, but lets leave that. As far as batteries concerned, it doesn't really get much easier.

However, bottle cage (bidon) mounts are pretty weak. Side impacts from minor benders/mistakes can lead to pulling them out of the frame. I modified my battery mount to primarily rely on hose clamps around the frame instead. More effective and allows the battery to slip if its hit from the side, which is better because its less likely to damage the battery or the frame.

I'd get the dimensions of the batteries you are considering and make cardboard models to make sure they not only fit, but can easily be taken on and off the bike without fouling on the frame. The ability to charge off the bike is really, really underrated when it comes to charging at work. Being able to quietly charge the battery away from where others frequent is a major advantage and is just safer all round.

I've discussed the dolphin pack in detail in a thread I wrote about my commute bike.. search function should be able to find that if you are interested.

Further, I've also done a thread about a q76r frame build, which I think I posted all the calculations for figuring out battery sizing in. Should also be handy for you.

I'll keep out of the vendor squabble. You should thoroughly research the vendor you choose to deal with and ask yourself not only whether their products are like, but what their service is like in the long run and whether they are close enough to you to use local freight. Up to you.

 

[Lurkin]

Couple of other things while I'm thinking about it:

- Unless you are concerned about weight, oversize your battery. Li Ion does loose capacity over time and it doesnt hurt if your battery is bigger than required. You may also enjoy taking longer trips from time to time and extra capacity is required.
- Using dolphin packs is also cool because you can swap out another pack with a different capacity at a different time, allowing for pack changes on really long trips.
- Take care calculating how much of the charge you will use each anticipated trip and how long it takes to charge it again. Then look to your available free time and consider whether you are able to supervise charging in that time. I found my pack takes way longer to charge in full than I thought it would (I didn't do the homework to know the time it would take) and consequently I constantly run into the issue of the pack taking too long to charge before requiring it to commute with again.

 

[Lurkin]

Lastly, if your worried about capacity, consider what speed you really require. The lower the speed, the smaller and cheaper your pack size is.

My commute is 80km per day. I achieve this with a smaller pack than you will, because I travel slower and use less energy to do so. Speed and voltage are related. The higher the speed, the higher the voltage required, the bigger the pack.

The nominal (think average, normal) voltage of one cell is about 3.7v and they have an individual capacity of 3500mah. To get higher voltage, you connect cells together in series. This leads to a higher voltage, but the same capacity. To get 48 volt nominal, you need 13 cells in series, known as 13S. 13 x 3.7 = 48.1v BUT your capacity remains 3500mah (3.5ah).

Compare that to 36v. 10 x 3.7 = 37v being ~36v with 3500mah capacity. In other words, you need less cells to make the required voltage, with the same capacity.

Given you are looking at a 17.5ah pack, 17.5/3.5 = 5p. This means the pack you intend to buy should be 13s5p, being 5 packs of 13 cells in series. Another way to view that, is that it is a pack made of 65 cells (13 x 5).

The same pack size at 36v will give you 6p (rounded down). 6 x 3.5 = 21ah.... food for thought anyway right?

 

[Lurkin]

I'd welcome the idea of comparing packs from various different vendors. It's something I've been wondering about for a while - I have no idea of what's actually inside this dolphin pack as I've never disassembled it. I was waiting until the cells have lost a useful amount of capacity before disassembling. By then it will probably be too old and the techniques used to assemble it will be old hat by the time I get round to it.

I'm not sure if a vendor is the best person to do it due to lack of independence, but then, who else will actually fund this activity? Its an expensive idea/exercise and I don't see anyone other than a vendor having the motive and funding to do the review.

I have tried to suggest that vendors should be actively promoting what they are doing and their developments in a specific part of the forum. AW advised the Resources & EV Related Parts and Services is the correct area... but I suspect its been a pretty long time since anyones really used it that way and certainly the bigger players are not interested. I'd certainly be interested in reading up on what Luna has been doing/interesting developments.

Similarly, my offer to update the wiki with information also remains open... no vendors have supplied me any information to date.

Threads here if your interested Eric: https://endless-sphere.com/forums/viewtopic.php?f=26&t=84063#p1230643

To a certain extent, either way,

forum users need vendors....
vendors need forum users....

Going at each other achieves little to nothing. Working together has the potential to create something greater than the two groups individually.....

 

[999zip999]

Price and usa based. They are other new us based companies coming soon. I think the op would need a 24ah battery , it's all riding style "terrain and weight. And as dogman says that one windy day.

 

[youyoung21147]

Having built a 14S 5P pack based on NCR18650GA (that is a 48V 17.5Ah pack), here is my feedback :
- 80km autonomy is totally doable. I do it on a regular basis in 3.5h with 1200m positive slope on a MTB with Xofo MMS mid drive. That's about 32km/h average on road parts, much less off road.
- You won't be able to do it more than 30-60 times : the GA cycle life is terrible if you cycle them that hard.
- 840Wh is a false claim : you will never be able to extract all this energy from the pack in an ebike context. You can expect 650Wh (reasonably and reliably usable) from a new pack but don't count on more or expect problems ! Luna cycle is a liar in this regard, just like the big names Bosch, Shimano, Yamaha... advertising "500Wh" batteries.
- Take care of the pack : don't fully charge (>4.10V), don't fully discharge (<3.2V), keep balanced, keep cool, don't store it charged, charge very slowly (<2A), don't use bulk chargers, don't trust integrated BMS, invest in a quality balance charger. A well treated pack should last for 10 years with >500Wh capacity available when you need it.

 

[DingusMcGee]

youyoung21147 ,

you say:

- 840Wh is a false claim : you will never be able to extract all this energy from the pack in an ebike context. You can expect 650Wh

I have build 11 battery packs from scratch [bare cells] and have maybe 6 Luna Cycle made Packs. My experience with all these battery packs concurs with what youyoung21147 has said in that for the purpose of ebike context you can figure no more than 80% usable energy of the rated capacity. youyoung21147's usable energy percentage is 650/840 = 77.4%. After you use up that 80% the batteries still have energy but the instantaneous on demand power is far down from what it is when the batteries are fully charged. In fact not enough amps? to start the ebike. The 80% usable energy is applicable also to the ratings of my SLA AGM batteries in my EV plug in car and the batteries in the solar cell setup.

If a customer hopes to get 100% energy out of the battery[dream on] as that much draw down greatly shortens battery life and may ruin some lithium cell membranes.

My personal thoughts on advertised total battery energy is that a lithium battery making vendor's energy declaration is fair to us when he claims an energy output equal to the sum of the lithium cells he uses in the declared battery based on the cell manufacturer's public data of that particular cell's energy. It would be a bonus to us if the pack maker could tell us more about the packs shortcomings -- Chinese cells.

 

[ScooterMan101]

First , Where do you live ?

Good to know for knowing the kind of terrain you will be riding, and possible places to buy a battery from.

>

Now instead of getting into the , where to buy the battery from discussion , I will just tell you what I would do in regards to a battery pack, having made the beginner mistake regarding batteries that I made 2.5 years ago. ( I bought a generic rectangular 48volt pack encased in a aluminium case made for the cheep low watt hub motor e-bikes )

Now , if you are going to operate/ make a e-bike conversion using a small motor like the Q100 / Q100c CST , etc. under 450 watt motors,
then I would consider using the GA cells, ( they are advertised at 3,500 mAh per cell, but some people say they are really 3,400 mAh per cell )
and even if you do use such a low watt / power motor, I would still not use a 2 p battery pack, 3 p minimum and more like 4p or 5 p pack really to get some life out of the pack, remember you only want to use a percentage of any battery pack you buy.
For people using the lower power / watt motors , the GA cells looks like a great battery.

However ...

If using a motor that is rated and you are going to be using over 450 - 550 watts from the motor like the 1,000 watt one you want , then I ... Would NOT , use the GA cells. I would use a cell that has a higher continuous amp draw rating, I can not tell you exactly which ones, the Vendor will tell you that, look for the words
" High Power / Amp Draw" rating. they have less mAh per cell, but will last you longer, when pulling allot of amps , and be more of a Real Total Watt Hour Rating. More believable in terms of how many ... Usable ...Watt Hours the pack has/ really is.

Hello everybody.

First post but I read hundreds of them. Thank you for helping me to slowly climb the learning curve. Battery chemistry can be really confusing sometimes.

After an extensive research I am planning to buy my first battery and my first option is the Luna Cycle Jumbo Shark Panasonic 18650 GA 17.5ah - 48V

To narrow the search I used this parameters:

- Has to be a dolphin/shark fixed to the frame as it will be my first ebike and do not have the experience to buy the cells separately.
- Besides that, I will use it almost every day in short trips to the office. It is a flat 10km route each way.
- Totally safe and easy to use (no LiPos).
- Would it be too much to expect around 80km of range (flat route) at 32km/h (20 mph) with 50% assistance? During the summer I use my road bike and I would love if my wife can keep up with me using this kit, that’s why I need the battery to last at least 80km.



I considered other options like Em3ev but the dolphin packs they list on their website give no more than 680 watts per hour instead of the 840 wph coming out of the Luna Cycle pack.

Sorry to ask you this question but I cannot manage myself to understand and use properly the ebike.ca calculator. Do you think I can reach the requirements from the last point in the list above with this 17.5ah 48V Panasonic GA pack?
Can somebody clarify what would be the range and speed at full throttle?
I believe that the closest battery in the simulator is the one named "48V 20Ah AllCell".

I do not have the engine yet but most probably will be a Nine Continent 1000W rear hub motor.

Thank you very much for your help, it is really appreciated.

 

[Hillhater]

However ...

If using a motor that is rated and you are going to be using over 450 - 550 watts from the motor like the 1,000 watt one you want , then I ... Would NOT , use the GA cells. I would use a cell that has a higher continuous amp draw rating, ......

??? The OP is asking about a 17.5 Ah pack of GAs. That would be a 5p pack .
Even at the max of 1000W, that would only need 20A @ 48v,....or 4A , (1.2C). per cell. Perfectly doable for a 10A rated GA cell.
....and that is a Intermittant MAX amperage which he wont be able to use if he wants to get 80km ( or even close) from the pack. At 450-500 W it will only be drawing ~ 2A per cell (0.6C) ......so why would GAs not be suitable.?
The OP needs maximum capacity, not power output , so a higher capacity cell like the GA is a suitable choice...
.....but i still think he will need 20-25Ah to achieve 80 km reliably.

 

[Samd]

There is some good data but this thread is heading more for opinions. Danish battery tester Dampfakkus shows good charts of 10a and 15a per cell - the 15a heats up fast so presumably damage occurs to the SiO layer. Precisely what temp is not known.

I can't post the charts from my phone.

There's a rehash of the various opinions in this thread.
https://endless-sphere.com/forums/viewtopic.php?f=14&t=70147

If the OP wants a bbshd or bbs02 it would seem like at least four parallel strings are a good idea based on the data.

Cycle life is a risk at ten amps. If you buy a pack look for a one or two year warranty. If a shorter warranty is offered factor in risk of pushing a high density cell with high amps.


Sent from my iPhone using Tapatalk

 

[Hillhater]

There is some good data but this thread is heading more for opinions. .....

..very true samd,..and you have just added to those opinions ! :lol:
The OP aked if a 17.5 Ah GA pack wold give 80km of easy roadwork.
..10A, 8A, etc were never in consideration, so why are they being debated. ?
If he is going to make 80km , then he can only average 5.5 A at most ....less than 1.5 A per cell (0.4C) !
And even if he does hit the hill with the full 1000 W burst , that still only 4 A per cell !
GA is certainly not the best cell available, but it is a fair compromise on $$/Ah for this type of application.

 

[youyoung21147]

There is some good data but this thread is heading more for opinions. .....

..very true samd,..and you have just added to those opinions ! :lol:
The OP aked if a 17.5 Ah GA pack wold give 80km of easy roadwork.
..10A, 8A, etc were never in consideration, so why are they being debated. ?
If he is going to make 80km , then he can only average 5.5 A at most ....less than 1.5 A per cell (0.4C) !
And even if he does hit the hill with the full 1000 W burst , that still only 4 A per cell !
GA is certainly not the best cell available, but it is a fair compromise on $$/Ah for this type of application.

Sure, GA is ageing too fast even in shallow cycling ! Cells like NCR18650PF or BE have lower capacity but a flatter cycle vs capacity derating curve

After 50-100 cycles they have the same capacity.

 

[radix]

I'm considering a similar 48 V 17-17,5 Ah dolphin/shark form battery pack as op. The cell options are NCR18650GA 3500 mAh and NCR18650B 3400 mAh. These cells are available in 13s5p dolphin/shark form. Because I pedal a lot, continuous discharge current is going to be only 0,2-0,4 C (0,7-1,4 A / cell). I’m also going to charge slowly at about 0,1 C and usually to 4,1 V / cell. Which one of these cells would give the best cycle life with such low currents? I haven't found any low current cycle life tests. GA 3500 mAh would provide a bit higher voltage at the same currents than NCR18650B, but cycle life is be more important to me.