LI-ion NiCoMn Battery from BMSBattery

I feel like a traitor, not just getting another Ping. Nothing wrong with the Pings I have, but I want to be able to take a 100 mile ride without any charging. I've been looking at this chemistry for a while and wanted to try one. Haven't seen much in the way of reviews, but it is supposed to be about as "safe" as LiFePO4. It is only rated at 1C continuous, but for the last year and a half I've been using a 48V 10AH Ping and this one is 48V 20AH. I do like the BMS on the Ping with the LED's. The BMS on this battery is completely hidden within the heavy tube shrink wrap.

The battery took less than nine full days to arrive from Hong Kong to my door, shipped via DHL for USD $488.64 total. It arrived well wrapped and in good shape. It had a charge of 53.6V. The charger boosted it to 53.9 in about 5 minutes and then shut off.

On their specs page this battery was listed as weighing 4.8 Kgs which would be about 10.5 Lbs It actually weighs almost 14 Lbs. The dimensions were accurate and hopefully all other specifications are also accurate.

The charger, charging wire from the battery, and main controller wires from the battery all came with those standard 3 prong appliance connectors. They included an additional one to use on the mains to the controller. The plugs for the charger are reversed from the plugs for the power to help prevent accidents.

I'll wire it up and put it on the trike tomorrow. It'll take a while to break it in gently before reporting sag and capacity details.

Rassy said:

It is only rated at 1C continuous, ...

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That's strange. Most Nickel Cobalt Manganese cells have a 5c continuous and 10c burst rating.
1C continuous is usually for 18650 LiCo cells.

SamTexas said:

Rassy said:

It is only rated at 1C continuous, ...

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That's strange. Most Nickel Cobalt Manganese cells have a 5c continuous and 10c burst rating.
1C continuous is usually for 18650 LiCo cells.

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Any NMC cell in 18650 was made for a laptop, not an EV. It's going to have very little material in it to improve conductivity.

I have never seen an NMC 18650 cell for laptop. Does it actually exist?

This battery is supposed to be made from 4P13S 5AH Polymer Cells. The charger is set to 54.6 max which brings the battery to about 54 volts, or just a little over 4 volts per pouch. Most of my use will be at 1/2C or less (10 amps) so I do expect to get the full KWH out of it. But it will be at least a few weeks before I try to push it much beyond 50% dod.

Interesting! been curious about these for a while awaiting your tests

1C is pretty pathetic and will sag pretty hard even at 1C. Still, interesting to see how these go for lower power stuff. They could be a great battery for a starter ebike kit.

NMC / liMnNi is often really uber low discharge stuff... more comfortable at less than 1C. High discharge stuff is the exception rather than the rule, and is usually found in mass-manufacture electric cars.

oh dude, that sucks about the weight. Now i've lost interest, officially.
For reference.. 20AH of 48v 20C lipo is about 15lbs.
Without the BMS and wrapping/padding, that's probably 13lbs.

NMC exists that is within the 200wHr/kg zone.... this stuff sure ain't it. This is prolly more like 170wHr/kG versus ~150wHr/KG for lipo. I'm interested in the 200wHr/kg stuff.

Cannot argue with the price however. equivalent hobbyking lipo would cost you $418 plus china shipping... then you wouldn't have a bms, wiring, padding etc.. that's another $100.. then you'd need a charger, that's another $100 + whatever a power supply costs.. that's about $600.

a 48v 20ah ping would cost you $600 and you'd only get a 2A charger with it. Plus the battery would weigh 22 pounds.

This bmsbattery pack is a good deal.. let's see how it performs when you put 10a and 20a loads on it..

The cells themselves probably are about 200wh/kg. But when you add all the weight of the tabs, solder, wires, connectors and BMS not to mention shrink wrap and any badding they put in the pack then you wave goodbye to the 200wh/kg rating simply because it is no longer a bare cell, and all the additions only add weright and not any power, in fact, the BMS probably reduces the useable capacity/power somewhat.

You cant really weigh a fully built up battery pack and expect it to have 200wh per kg of weight.

As good as their chargers and controllers are, they are so optimistic with advertised battery weights.
The 48/12 headway had over 7kg instead of 6kg as advertised. 14lb instead of 10.5 is flat out rude.
Especially after you've paid all the money for shipping and there's no sensible way of returning the item.
Smells Chinese.

I'm not bummed out about the weight, because I saw the inconsistences when comparing their 10AH, 15AH, and 20AH batteries, so expected it to weigh about what it did. An equivalent 48V 20AH Ping battery is about 50% heavier.

Also, at 2 1/2 inches wide, self contained BMS, and wires coming out of one end, this would make a great candidate for mounting in the triangle, provided if performs as expected.

I realize this would never be the battery for a high speed high power rig, but on my trike with a 300# gross weight (including me) I can go 20 MPH on the level and climb up to a 10% grade (at a lower speed of course) without pulling over 10 amps. Even a 20% grade at 5 MPH only pulls 20 amps.

theRealFury said:

The cells themselves probably are about 200wh/kg. But when you add all the weight of the tabs, solder, wires, connectors and BMS not to mention shrink wrap and any badding they put in the pack then you wave goodbye to the 200wh/kg rating simply because it is no longer a bare cell, and all the additions only add weright and not any power, in fact, the BMS probably reduces the useable capacity/power somewhat.

You cant really weigh a fully built up battery pack and expect it to have 200wh per kg of weight.

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No, you can't at all. You have to add a pound or two for materials.

These are polymer cells, thus they are flat prismatic type. the interconnections are not going to be heavy at all. connections, bms, and packing materials would be 2 pounds at the very most here.

This would be 170whr/kg at the best case scenario.

Mystery to be solved here, because the 48V 10ah battery has a 2c continuous rating http://www.bmsbattery.com/48v/166-48v-10ah-lithium-ion-electric-bicycle-battery-pack.html Do you suppose the batteries are 2c (or more) capable, but they're using the same stupid one version fits all BMS on the 20ah version?

Gary

Actually their discharge specs are all over the place for those packs. I think they don't even know what the real discharge specs are.

As with all discharge/charge rating on batteries, take it with a grain of salt and assume that you'll have to run it at half that.

Starson said:

Mystery to be solved here, because the 48V 10ah battery has a 2c continuous rating http://www.bmsbattery.com/48v/166-48v-10ah-lithium-ion-electric-bicycle-battery-pack.html Do you suppose the batteries are 2c (or more) capable, but they're using the same stupid one version fits all BMS on the 20ah version?

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I bet that's it. Good observation!

I agree, good observation on the discharge rate Starson.

I'm going out of town tomorrow, so may be a few days, but I think voltage sag under different loads will be a good indicator of the capabilities of the battery.

It could be that they just copied the same text for all the batteries, since the 48v 10AH, 48V 15AH, and 48V 20AH all have the same discharge rates. So hard to tell which one these discharge rates really apply to.

Is a voltage that low normal for a fully charged NiCoMn? A 48V nominal LifePo4 charges up to about 60V.

Really curious to see how much sag you experience. What controller are you going to be using?

NeezyDeezy, I can't really answer the voltage questions yet. This battery is only 13P while the LiFePO4 is 16P.

What controller are you going to be using?

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The controller is a 6 Fet Shenzen by ECrazyMan that I purchased from JohnRobHolmes for a Bafang and is now being used for the 9C 6X10. Battery input limit is about 23amps

An ES member itselectric sells NiCoMn batteries, but I've never been able to locate detailed pack/cell specifications on his site http://us.itselectric.ca/LiFePO4_ebike_Li_Ni_Mn_Co_02_NiCd_NiMH_Phosphate_s/48.htm I don't know if they are the same cells as bmsbatttey uses or if the cells he sells (on the seashore) have different capabilities?

Gary

hhmm... 6.2lbs is a bit heavier than 20C RC lipo ( 5.6lbs ).. some of that weight is probably BMS/packing.. but...

Their testing regimen is also weird and really says nothing about the performance of the pack.. how many C it can put out etc
I now understand why i never heard of this battery before.. lol

Got the battery installed on the trike today and took a nice little ride. Used 292WH to go 13.3 miles, so pedaled less than normal and rode a little faster. I was busy watching the Watts Up meter. Following are some measurements:

Resting voltage before the ride was 54V, a day and a half after being charged
Resting voltage after the ride was 49.5V
Voltage sag in the 15A range was about 3V
Minimum voltage was 46.2V, but I ended my ride with a short 20% grade driveway
Maximum amps at the battery was 21A
4 amp charger was right on, at 1hr 35min to replace 6AH

I haven't seen discharge characteristics on this battery, but it appears to have a continuous voltage drop, somewhat like an SLA. Longer rides will confirm this, but that may take a few days since rain is on the way.

Took a 20 mile ride today and collected some data. Unlike yesterdays ride, I rode slowly and contributed more through the pedals, like when I ride with my pedal only trike buddy, and seldom pulled over 6 amps.

Total AH Used-----Resting Voltage-----Total WH Used-----Total Miles

------0-----------------53.8------------------0----------------0
------1-----------------52.9-----------------53---------------4.4
------2-----------------52.1----------------105---------------7.6
------3-----------------51.3----------------156--------------13.6
------4-----------------50.7----------------206--------------19
------4.9---------------50.1----------------247--------------20

A couple of comments: The last mile includes the hill to my house, but something doesn't seem quite right since .9 AH should be less than 59 WH when under 50 volts. Perhaps I made a mistake on one of the numbers. Also, the voltage drop per AH used seems to be decreasing the more the battery discharges, and this is consistent with yesterday's result where I ended up at 49.5 volts after using 6 AH.

After I feel the battery is ready I'll do some longer tests, maybe not recharging each day and see whether the battery or the controller hits LVC first.

Thanks for posting your experiences, it's helpful.

That voltage sag is actually not too bad. I thought it was going to be a sag-o-rama pack.

As for your voltage curve, you can expect it to be somewhat like any other 3.6-3.8v nominal cell.

Fairly steady slope from 4.2-4.10v down to 3.3-3.6v, then hits a cliff and starts diving towards 0V rapidly.

Well at least it works, unlike the dead charger they sent me!!!


EDIT........................

Apologies to bmsbattery!!!!!

It was ev assemble who sent me the dead charger!

Bms battery sent me a working charger!

By the way my 16S 10ah LiPo weighs 6kg maybe 6.5, I forget so there is no weight advantage at all and I thought this nmc stuff was supposed to have around 1.5 the energy density ?

I'm a LiPo addict!