Thoughts on this battery?

BatteryMan

10 mW
Joined
Oct 10, 2016
Messages
23
I'm ready to build my own e-bike, I'm using a bike I already have and I'm going with this kit:

Passion 48V 1500W Electric Bike Conversion Kit

https://www.aliexpress.com/store/product/Passion-Ebike-48V-1500W-Bicicleta-Electric-Bicycle-Bike-conversion-kit-Rear-wheel-motor-kit/1088910_32476876343.html?spm=2114.10010108.1000023.2.XKRxF1

hub motor Max Speed: 600RPM
electric wheel Power: 1500W
hub motor Max Torque: 35N.M
High Quality 18 MOSFET 45A ±1 Controller
Full Speed: about 55-65km/hour (34 to 40mph)



The battery I plan on using with this setup is the 48v Panasonic 11.5ah or 13.5ah Shark Pack found here:

http://lunacycle.com/batteries/packs/48v/48v-panasonic-11-5ah-or-13-5ah-shark-pack/


My question regarding this battery pack is will it be enough for a 1500 watt motor?

The more I ready about batteries the more I confused I get. I keep reading about watts per hour, meaning a 48V battery at 11.5ah is 552 watts (not even close to the 1500w rating of the above motor). So do I need a 48V 30ah battery? 48v x 30 ah = 1440 watts, close to the 1500w rating.

The reason why I am thinking of purchasing the the Panasonic Shark Pack battery is because:

1) It's 48v
2) It's small, I have a mountain bike and plan on mounting it upside down underneath the lower beam of my bike. To explain it better, most bikes have an angled water bottle holder on the downtube, mine is there as well but it's mounted from underneath, closest to the ground. I figured this would be a better location then on the rear rack.
3) My route is 99% flat, although there is one big hill where I have to put my 24 speed bike into 1x1 gears in order to go up at like 2mph. The hill is maybe 1/8 of a mile.
4) I don't need a huge range, the most I would need is maybe 14 miles total round trip and I would never even go that far using the motor 100% of the time.

I would prefer a "dolphin" battery as it would be easier for me mount if you guys think there is a better choice for me.

Also, so I don't have to start a new thread, what is the easiest way to paint a dolphin case? My bike is red and most cases are black, I'd like to paint it red to give it a more stealth look.

Thanks for any advice.


EDIT:

What exactly is the difference between:

Long Range NCRB 13.5ah $20.00
High Power and Long Rage GA 14ah $60.00
 
The watt hours (552 for the 11.5ah) is a measure of stored energy, these batteries are able to deliver more amps than 1C. An 11.5ah pack with a C-rating of 1C would only be able to deliver 11.5 amps, 2C would be 23 amps, ect. The "high power" cells that luna offers have a higher C-rating than the "range" cells they offer. If you have a 1500W controller (30 amps) I would suggest the high power cells, although the other cells would be sufficient they would also be more stressed and thus not last as long. You can read more about 18650s online but it looks like luna has a bit of info on their website
 
The motor size doesn't matter. Only the max amps pulled by the controller does. The controller is the only thing that draws power from the battery. The motor could be 500W or 5000W, It doesn't matter. This is covered here.
https://endless-sphere.com/forums/viewtopic.php?f=3&t=66302
Personally, I would never buy a battery pack made up of 18650's, but that's what the hype is now. If your controller is 30A or less, it will probably work ok. Good luck.
 
I use the Luna 48v, 13.5ah, GA cells, shark battery pack, it is 13s and 4p, 13 cells in series and 4 13 cell sticks in parallel. The battery is carried on the rear rack. There is a plastic cutting board on top of the rack and a Harbor Freight 15" tool bag on top of the cutting board. The shark battery pack came in a box with foam padding, this padding is now on the bottom of the HF bag, the shark battery sits on top of the padding. This bag has room for the battery, a Kryptonite New York Fahgettaboudit Mini U lock and a surprising amount of groceries. The battery is on the rear rack, atop padding, because I did not want sharp jolts from the frame going into the battery, also the battery is expensive, so I wanted it to be easy removable, so it can go into the stores with me.

So far, this battery and the Luna Advanced Charger have worked perfectly for my riding, but I don't use anywhere close to 1500 watts. My bike path rides average about 9.5 mph and average 120 watts power use. Street rides are at higher average speed and higher avg power use. Bike path rides are done with a lot of pedaling, street rides use pedaling on the climbs. So, I do not know how this battery would do at high power outputs, since I ride at lower power output.

1500 watts will probably power an ebike at well over 20 mph, perhaps even 30 mph top speed. Let's look at that: 1500 watts / 48 volts = 31.25 amps. 13.5 amp hours / 31.25 amps = 0.43 hours, aka 26 minutes. .43 hours x 30 mph = 12.9 miles range, aka not much range.

Realistically, you won't ride at 1500 watts power, as others pointed out, there is battery maximum power output and there is motor maximum power output. One or the other, will limit the maximum power output. Besides that, power output depends on how fast you ride and the power consumption of the bike you ride. For a given power output, you will go much faster and farther on a road bike with 120 psi tires and using aero bars than with a fat tire bike, riding in an upright position. The difference in power consumption vs speed is pretty large, for these two different riding configurations.

Units, etc.: Volts is a measure of push the electricity has. Amps is a measure of the flow of current (electrons). Amp hours, ah, is a measure of battery capacity, but it neglects the very important voltage. Watts is a measure of power, 746 watts is one horse power. One HP is 550 ft lb per second, note: US units are more useful than metric units, for this kind of thing. Amps times volts = watts, this is a very important law of nature, current times push = power. Watt hours is a measure of battery energy holding capacity, example: 48v times 13.5 amp hours = 648 watt hours. Another note, just because the Luna GA cell, shark battery has 648 wh, does not mean you should plan on using all of them. Without harming the battery, about 60 percent is actually usable: 648 wh x 60%/100 = 389 wh usable ... without harming the battery.

Well, there are no conclusions, just pointers, hopefully pointing to the correct direction. Questions? Ask away? The only wrong question is the one that should have been asked but wasn't asked.

Bottom line: the Luna 48v, 13.5ah, GA cell, shark, battery pack has been most excellent for my application, as has been the Luna Advanced Charger. But, I ride at low power outputs, using an Aotema, brushless, direct drive, sensorless, front hub motor, with a 36v controller.

Ride on.
 
MikeSSS said:
I use the Luna 48v, 13.5ah, GA cells, shark battery pack, it is 13s and 4p, 13 cells in series and 4 13 cell sticks in parallel.
What is the BMS rated at? Please tell me its not more than 30 amps or so?
 
BatteryMan said:
Long Range NCRB 13.5ah $20.00

I don't think NCR18650B are suitable in an EV. (Unless it's an enormous P pack)
 
At seven amps a cell they can be good on a bbs01 at 4p.
I also made Sundrive a huge 12p pack for his stealth bike with them and got an extra 250 watthours for the price the GA would cost.


Sent from my iPhone using Tapatalk
 
I would say that 45 amps is pushing a shark battery too hard, even with GA cells. the killer whale one would be much better:

http://lunacycle.com/48v-pansonic-ga-17-5ah-black-killer-whale-ebike-pack-huge-range/
 
I need some advice on a battery for a 48V 1000w electric kit. I plan on buying this kit:

https://www.aliexpress.com/item/Passion-Ebike-48V-1000W-Electric-Bicycle-Fat-Bike-Conversion-Kit-Black-Blue-Yellow-26-Wheel-Motor/32675462539.html?spm=2114.10010108.1000013.6.iQCe07&scm=1007.13339.33317.0&pvid=265001d5-3704-4b05-9479-19549447ca99&tpp=1

And after spending hours of research this is the battery I plan on using:
https://www.aliexpress.com/item/passion-ebike-48V-11-6Ah-electric-bike-battery-Bicycle-Parts-Battery-for-Panasonic-29PF-Cell/32648849643.html?spm=2114.01020208.3.1.97pHi7&ws_ab_test=searchweb0_0,searchweb201602_1_116_10065_117_10068_114_115_113_10084_10083_10080_10082_10081_10060_10061_10062_10056_10055_10054_10059_10099_10078_10079_426_10103_10073_10102_10096_10052_10050_10051,searchweb201603_2&btsid=bdb582bf-6c9e-4ec0-8e17-c0079902e643

Any thoughts on the battery? The specs in the battery state: Discharge Cutoff Voltage (V) = 40+/- 1V

Does that mean I won't get the full 48V out of my electric motor?

I was also looking at this battery here:
https://www.aliexpress.com/item/Hot-selling-Samsung-48v-lithium-ion-battery-for-electric-bike-48v-11-6ah-new-bottle-battery/32358991471.html?spm=2114.10010108.1000014.10.ibMQtb&scm=1007.13338.49930.0&pvid=4b99e3a7-8dcf-47c6-8770-d1dd5202727d&tpp=1

But that battery says that it's discharge voltage cutoff is 39V.

If both of those batteries are no good what would be a good battery from Ali Express? Also, I'd like to keep the cost down and don't want to spend half a grand on a battery.
 
I bought the cali 20amp and it has been great. they have a 15 amp also

http://calibike.com/product/48v15t-electric-bicycle-ebike-48v-15ah-lithium-triangle-pack-battery-and-charger-1-yr-warranty/

He is easy to work with and shipping was very fast.

Keith
 

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So the battery I plan on purchasing comes with a 2a charger and takes 7 hours to charge to 100%. From everything that I've read the sweet spot for charging batteries is up to 80%. So instead of spending $100 on a smart charger that charges up to 80% for you I want to do it manually. The battery has 4 lights on it indicating how much juice is left:

1) Red
2) Orange
3) Half Green
4) Full Green

My question is how long should I charge the battery on each of the 3 settings (except full green of course) to reach 80% capacity?

According to my math:

1) Red = charge for 336 minutes to reach 80% capacity
2) Orange = charge for 252 minutes to reach 80% capacity
3) Half green = charge for 168 minutes to reach 80% capacity

Does that sound about right?
 
You don't provide enough information to suggest a response. But I don't and would never use such a data-void technique. I use Celllogs to accurately display voltage for each cell in my battery pack during the charge cycle, with alarms set for over-voltage. I've set them to trigger at 3.62V, an optimum high-voltage for LiFePO4 cells, and yielding upwards to 90% of capacity. More than anything, over-voltage of cells will degrade cell longevity, so to be avoided. And is more physics than math.
 
If you don’t know the charge profile there’s little accuracy using time based capacity analysis.

Bulk charge (the majority of capacity) can often be completed in a fraction of the time it requires for the last 10% SOC. And perhaps much longer if some balancing is going on, etc.

Another thing is that those LED “meters” are notoriously inaccurate. Maybe not even calibrated for the chemistry you’re using?

Get some actual gear, celllogs, rc chargers, power meters, etc., in order to more fully understand care & feeding of battery packs.

Short charging might improve longevity but at the risk of OD (over discharge)? Just one of those events will toast most lithium cells.

Main thing to avoid is leaving packs sit at full charge. Momentarily charging packs full and immediately using them is much better than fully charged and then sitting around for a week.

Moral of that story is to only partially charge if you’re not sure about using it the next day. Then when you decide to ride, finish off the charge and go have fun.
 
Ykick said:
... Short charging might improve longevity but at the risk of OD (over discharge)? Just one of those events will toast most lithium cells.

Main thing to avoid is leaving packs sit at full charge. Momentarily charging packs full and immediately using them is much better than fully charged and then sitting around for a week. ...
Good advise. Its what I do - leave my pack in half depleted state after a ride, and only charging just before I embark, to 80-90% SOC. My rides don't carry me far enough to risk over-discharge, but during those few times that I might I take my charger on the road with me and charge when I feel that decrease in speed that results from too low voltage.
 
Most battery problems come from a person forgetting to charge a battety after use and the bms drains a cell to low usually s
Cell one through three. You need to have charge in a battery or else.
 
Run it to 100% full, then discharge to 80% full.

Without a wattmeter, yer just guessing.

With a real voltmeter, then you can get a volts number to aim for. Still an approximation, but a very close one.
 
I bought 4 ORBTRONIC 3400mAh 18650 PROTECTED 3.7V Rechargeable Li-ion Batteries and a Fenix ARE-C2 four bays Li-ion/ Ni-MH advanced universal smart battery charger.

1) When charging the batteries the charger gets warm/hot, is that normal?

2) The readout on the display says the 3.7 V batteries are charged to 4.2 V. Is that normal? If the batteries are only 3.7 V why is it charging them to 4.2 V?
 
I find it ironic that the BatteryMan is asking questions about batteries :)

1) Yes, all electronics are inefficient and they all get warm, even if most are imperceptibly warm.

2) Batteries are most commonly rated by their "nominal" voltage. Nominal is the voltage when half the energy is used. So 4.2v is fully charged, 3.7v is halfway down, and depending on exact chemistry, empty can be anything from 3.5v to 2.5v.
 
Battery man needs to go to battery university.

Though much of that website is pretty old, it's still a good place to get the basics. They explain watts and amps well, and other stuff that's pretty hard for us mere mortals to grasp at first. Ohms law,, oh joy for most people.

We don't mind answering the basic questions over and over that much, but there are some good places to read first.

Grin Technologies basic e bike tutorial pages are very good. And a bit less easy to read, ES has a half complete wiki section, and the technical reference section.

To clarify your original question, all chargers get warm. More powerful ones get hot, and need to have the fan inside blowing when they push current.
 
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