Hands on Test : 48 Volt 20 AH LiFePO4 pack from Ping Battery
Just got the 48V 20 AH LIFePO4 battery from Li Ping in China yesterday. Only took one week for it to get the SF Bay Area. It came with a 2 amp approx 60 volt charger. The battery is very compact-about the size of 3 12V 12AH batteries side by side. I get 5.5 inches X 4 Inches by 14 Inches. Weight is under 20 pounds.
I am running it in a modified Lashout scooter with the 48 volt 1000 watt brushless motor set up from Powerpack. The controller is a true 35 amp continuous. With a set of 12v 10.5 High rate Lead Acid batteries, I could go 29 MPH top speed, and ride at full performance in my hilly area for about 5 or 6 miles. Then it would go another couple of miles at reduced speeds. OK for running about the neighborhood, but not enough range for some serious errand running. I live where there is many 10 to 20% grade hills, some of them very long.
My goal with the Lithium pack was to extend the total range considerably, and also to knock 10 to 15 pounds off the scooter. I also wanted to be able to go 14 or 15 miles with no drop in performance.
Li Ping from Ping battery custom set up the pack for me with my motor and battery box parameters.
The BMS is set for 38 to 40 amps continuous, with 60 amp peaks. Yes, it is wrapped in duct tape, but after just getting back from a 14 mile ride at full speed, I can say the batteries live up to the stated claims-and no bad smells either. I got tired of riding after 14 miles so I came in, and measured the voltage of the pack at the end of the ride to still be 51 volts. My guess is I could go 20 miles total no problems, tripling the range form the heavier LA batteries. What is even better, is that I could still go full speed at the end of the ride. I actually improved my top end to 32 MPH from 29. Li Ping also told me the batteries will increase in performance after a few charge discharge cycles. The scooter did not cut out on me at all, even going up a 20% grade.
These batteries are available in many sizes, and Li Ping will custom make one if you need something special. Anyone waiting for quality Lithium batteries at affordable prices can stop waiting. My only concern would be for folks running very high amp motors.(like an Etec) I don't know if these batteries could be arranged to supply the needed output for those situations. I guess if you could fit them and ran twin 48V 20AH packs, you could double the continuous amp output to 80 amps.
I am thinking about a 36 volt pack to run with the 350 Watt Bionx kit. Bionx told me they would sell me that kit less their outdated over priced Lithium ion 36V 9.5 AH stock battery.
I am also still looking into 100AH LiFePO4 cells for a 120 Volt pack to power a small classic sports car for a project I'd like to start in a year or so.
Andy, your report sounds good, but that end-of-ride voltage may not be indicative of the charge left, so I'm not sure you can actually say at this point the bike will go another 20 miles. I look forward to more reports.
I had been corresponding with ping about getting sixteen 40 AH cells and a BMS for 95 amps for my e-max. After several e-mails back and forth with various Q&A's, Ping stopped corresponding. Maybe I was asking too many questions.
I guess my grammar above needed some work. I didn't say I thought I could go 20 miles MORE, but 20 miles TOTAL =6 more miles. From the time it took to charge the pack, I bet there was at least 1/3 of the life still in it at the end of the ride.
Ping told me he can get the larger AH cells, (I asked about the 100AH electric car size) but that he specialized in the smaller ones at this point. I took that to mean he wasn't that interested in fooling with the bigger AH packs just yet.
I am just so amazed at the power reserve available now compared to what I have been running. It opens up a lot more uses for the bike now. This new battery technology may end up bringing major changes to the EV market. 20 mile range high speed small scooters, 50 miles or more range electric bikes that don't weigh a ton, 100 mile range freeway capable electric cars conversion kits where the car weighs the same or less than the gas powered version. I want one of those!
In answer to the question above, I also own a YESA 48v 12AH pack that cost more than the 48/20 does from Ping. Pings pack has way more power and capacity in my experience with them both on the same scooter, and of course it should being a 48/20. So far, its a way better deal. I didn't ask too much detailed info on what individual cells he used. He mentioned something about them being a "soft as opposed to a hard style" that YESA uses. The cells he uses are also more compact. YESA's 48/20 wouldn't fit in my battery box.
The "soft" cells are what is called "prismatic cells". They are like a foil pouch so you can pack more of them in a tighter space.
Regarding your contact with Bionx: Did they say they intend to market a 36V 20AH LiFePO4 battery using their current physical configuration?
Bionx only said they would sell the top of the line kit to me without any battery at all for about 1/2 the price of the complete kit. They do need to update their battery options in my opinion, but I do not know if they plan to anytime soon. That LION they supply is only a 36V 9.5AH and they get like a $1000 for a replacement! It is also only supposed to take about 400 full charges before it needs replacing. That is $2.50 a charge. If you rode nearly every day, you'd have to buy a new battery for $1000 every couple of years.
For me, a major attraction of the Bionx system is the physical configuration of the battery pack and its integration into the whole package. Maybe there's an opening for a start-up to re manufacture the battery case with LiFePO4 cells. How hard could it be?
from an engineering stand point, I am not sure that the two tiny 6mm threaded holes designed to hold a couple pound water bottle are the best way to fasten a 8 to 10 pound battery to the frame, especially on an aluminum or carbon bike. But what do I know. I wonder if anyone has had the weight of the battery pack bouncing around tear out the bottle bosses, especially on a mountain bike.
I don't recall how many individual screws are supplied with the kit. But I just checked and counted 5 recessed screw holes on the bracket. I used three on the admittedly unconventional setup on my Rans Rocket. (I didn't make holes in the frame).
To make matters worse, those 6mm holes for the water bottle cages are actually 5mm.
Hello andys, and thanks for posting the info. Is this the promised land? I've been running SLA for about 2.5 years, and have been patiently waiting for batteries that give good power and less weight. I currently run a 48v, 500w machine, that's fairly heavy with about 30ah's of battery in it. It's actually a motorino sold in Vancouver, http://www.e-ride.ca/Electric_Scooters/Motorino_XPi.html , and the range is limited to about 25km (I've had the controller set up for more torque than stock). I care less about the speed, as long as it travels over 30km/hr, but would like to increase the distance to something more than just work and back. Reliability, that's the question for me. Thanks again, and keep us posted.
hi, thanks for your post on ping battery. I have been corresponding with him. He certain ly didn;t answer all my questions, but enough for me to base a decision. He certainly seems reputable and honest. And he sent you replacement bms. His feedback is all good. My criteria for battery is cost and size. i'm glad I learned about the different bms for discharge 1c vs. 2c. and that his packs are nade of 5ah cells. and to go the extra mile and make the battery to fit my dimensions! A much better battery for the same price as sla? Well, he couldn't make me a 72v 5ah for 20a discharge and 20a charge, so I just purchased 3 of his resized 36v 10ah lifepo4 batteries w/bms and chargers included for $750 delivered. I will put 2 batts on bike, and attempt to reconfigure the extra 36v 10ah batt into 72v 5ah, and bypass or run without bms.
the battery not for this bike, this bike just look pretty...
Still enjoying the huge increase in range and the flat power curve of these LiFEPO4 batteries. I also just built an electric bike with the 48v 12ah Yesa pack that I first tried on my scooter with limited success. It works really well with the BMC hub motor from EV Tech. Electric assist bikes do not have the high continuous amp draw that a powerful electric scooter does.
Sounds like a good replacement. I'm just beginning to understand some of these "better battery" alternatives with regard to what works for what. I have the XB600 e-bike (actually scooter) from xtreme. It has a 600 watt brushless hub motor...don't know any specs for the controller...and it has 4 12v 20 ah sla batts. Does this mean, other than fitting the LiFePos physically into the battery space...that I could substitute one of these packs without any other alteration. Of course I'm assuming I might have to change the charging port to fit the supplied charger plug...or maybe not, and wire in the new pack. But do I understand that it might be this simple to make a switch? Or, am I missing something. I'd like to do this when the current sla pack goes south. Oh, also would changing battery tech effect whatever accuracy is in the charge gauge (indicator) on the instrument panel?
There is some minor wiring required to hook up these batteries, but nothing very difficult. They come with their own charger. The packs can substitute for LA batteries and everything will work as normal, except you will notice the charge gauge will stay green for a much longer range.
One concern is what the continuous draw is from the motor/controller on your bike. LIFePO4 battery packs do not like to go more than 2C on their continuous output. So a 48V 20 AH pack will not be able to keep up with more than 35-40 AMPs continuous draw. If the controller draws more, the battery will shut itself off. This is one area where the larger lead acid batteries have an advantage. Its a good thing to run your bike with a "watts up meter" or other metering device hooked up to it so you can see what the actual amp draw is before spending the money on the Lithium battery.
If you could run the 48/20 Lithium pack, you'd save about 40 pounds of weight on your bike, and probably go 25% further. The reduced weight helps with hill climbing as well.
I just thought I would share some info on these packs. Curiosity and a current application motivated me to order one of the 36 volt 20AH packs. It's comprised of 12 series cell groups of 4 paralleled cells each. I wouldn't want to try to reformat these into a different configuration or shape. They are assembled in such a way as to not be taken apart reasonably.
Here are the results of some testing. The BMS shut the battery down at 32 amps initially. Which is a little light for my needs. That's fairly easily adjusted by carefully changing the resistence of the shunt near the negative power lead. Once adjusted the fets held without significant heating at 45amps.
In a discharge test the battery started out at a standing no load voltage of 43 volts. The load applied was an average of 10.59A the test was ended when the voltage reached (pack at 32.5 volts) under load, or 2.7 volts per cell under load. The BMS did not end the discharge, I did.
Total AH drained from the pack was 19.57AH.
Standing no load voltage after a 10 minute rest period was 36.7 V
The recharge time was disappointing since the chargers are advertised at 2 amps. My equipment never measured more than 1.43 amps going into the battery. It was 17 hours before the BMS was actively engaged in balancing cells. It was 26 hours before the cells were fully balanced and each was fully charged.
This slow balancing is mostly due to the way the BMS works. It monitors each cell and and when one reaches 3.6 volts the BMS switches in a resistor across it But if it rises to ~3.75volts the charge current to the whole pack is interupted until the voltage falls back sufficiently due to the resistor loads. These long "off" cycles really drag out the balancing phase of charging.
Those resistors get pretty hot too, sometimes regitering 170F. I'd make sure that heat has someplace to go if using one of these batteries and BMS boards. Overall the discharge performance is good. However, the BMS is intolerant of faster balancing, but total charge times could be reduced by charging at a higher rate until the pack voltage is high enough that balancing becomes active. A two or three hour initial phase and then balancing with the factory set up would reduce the charge time in the test by at least 14 hours.
Hi, I received my 3ea 36v10ah ping batteries. I connected 2 to my bike for 80v10ah...No problems...the bike runs great...I connected my extra 36v battery to citybug e2 24v, 250w scooter, but connect to 40v ping battery...The scooter had high gearing, and so the battery kept cutting off, I couldn't get going...then I regeared the scooter, but since there is no controller, only relay to turn motor on, and slip the friction drive like a clutch, but still drew too many amps, and battery could not stay on...So then I went ahead and disassembled the ping battery, and separated all the parallel cells, so I make 2ea40v5ah batteries and connect together for 80v 5ah, nice and small, about 7lbs, remove all bms...the connectors on those 5ah cells in bags are really thin...I figured my connections would melt apart...I did't solder anything, I cut cell tabs with razor blade, and connect cell tabs with round 10ga crimps cut off the connector and flatten and crimp over thin foil pouch tabs...I took bike for ride...wow! It actually works! And then I did some full throttles and no melt or burn or smell...I will try charge with sla 36v charger later, and check individual cell voltages...I'm counting on them to stay in balance...
So to compare, I had a 72v 5ah capacity (9ah) 36lb battery for $250 only last 100-200 cycles.
And now I make a 80v 5ah 7lb battery for $250 that lasts??? 2000 cycles?
No comparison! I went from riding a bike feel like a motorcycle to now what feels like a bike with no batteries, but I have all this power! Now the ebike is fun again! Well, eventually I will put the 5ah 80v battery to the 20amp continuous test...I am so glad that the paper thin connectors held up so far...I wouldn't want to reassemble one of these batteries again, but it is very cool to have 80v 5ah battery for this price and only 7lb, Now, the thought of any electric vehicle with lead batteries is just absurd...the 40v battery is neat...after you ride some, the resting voltage actually goes up! After charging they both come up to 40.5v or so, and then mayde 41+v after riding...
In this post you mention that minor wiring is required. The pack I received has 3 wires; a heavy red and black and then a lighter green wire. I was told by the seller on e-bay that the wiring should be as follows but the cells are not charging but discharging is fine.
red + black connected to load for discharging.
red + green connected to charger for charging.
Does anyone think I've wired the battery incorrectly?
Since posting this question I've dismantled the bike and found this overheating/damage. Any thoughts on why this might have occurred?
Thanks for helping me out.
Hi Andys - I'm interested in running the ev tech bmc motor at 48v - could you let me know what controller you have, is it the stock one they supply?
I am running a crystalite 48 volt 20 amp controller. had to fabricate the couplers for the 3 phase wires, as the controller did not have the same as the hub.
I've emailed Ping a few times with some questions but I haven't got any replies. I hope he's not in the midst of the earthquake.
Maybe someone here knows the answers.
I'm interested in the 48 volt power pack.
Ideally I'd like it configured in a triangular shape rather that a rectangular shape. He mentions he can do other setups. Does anyone know the physical size of the cells so I can just arrange some dummies to see how to lay them out (if not wire them) to form a triangle?
What is the charge time using the 2 AH charger that is supplied and can I use a higher output charger to speed it up?
Are you sure about that the Ping batteries can't handle a 40a constant draw load? I'm using a Crytalyte Phoenix Cruiser that's 48v, 40a and I understood that Ping could build a battery to those specs. Has anyone here tried using one of Ping's batteries on that setup? Or a similar 48v 40a setup? Is the battery management set-up the cause of the cutoff issues under load? It sounds like some of you have removed the BMS to get yours to work. I'm no electrical wiz, but I really want to increase my range without spending a fortune to do it. The company I bought my kit from sells a 20ah Lithium Ion setup with BMS that they build themselves, but it's over $1500 which is more than the whole conversion kit cost, and just not affordable.
I'm also considering just waiting until Zero Motorcycles produces their new street bike. Their off-road motorcycle is balls-out awesome. It's got a 40-mile range, 0-60 in 4 seconds, 0-30 in under 2 seconds, and a two-hour recharge time, and it only weighs 140#. I'm guessing the street version will have slightly higher top speed with a longer range, which would be ideal. The off-road bike is $7500, but I could get rid of my commuter car if I had that, so it would almost be a wash on cost.
Here's the link in case you haven't seen it yet: