New alleged Panasonic battery failed to deliver in road test

Batteries, Chargers, and Battery Management Systems.
OzTrekker   10 mW

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New alleged Panasonic battery failed to deliver in road test

Post by OzTrekker » Sep 17 2016 8:31am

Okay so i purchased a battery from a well known business that shall remain nameless.

It was sold to me as Panasonic cells A grade 14AH 52volt.

There were some problems, the battery failed to arrive.
They stated some shipping problems.
Then they have a new office in Australia.
Then i receive the battery i paid "TOP DOLLAR" for without an invoice.
So then i protest and they email me an invoice.


So i test the battery, its not even producing ten amps.

So i write to them and ask for the following.

Type of panasonic cell?
Number of cells contained within the case?
The manufacture date of the cells?

Surprise surprise no reply.

My lipo batteries are a great yardstick, the 15AH lipo is what i calibrate these new batteries performance with.

This new battery is a disaster.

If it was a modular case then i could replace the cells.

I am worried that i am going to open up the plastic and find a glued mess of old reject cells.

Anyway i will keep you posted and send pics of the road testings.

At some point we all have to roll the dice on new companies that promise a quality product for quality.

I understand many of us have been in this position where we look at innovating new designs with new companies offering alleged quality parts.

Its the old adage wether they can back up what they say.

Any ideas on how best to dissect and test this product on youtube?

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Re: New alleged Panasonic battery failed to deliver in road

Post by OzTrekker » Sep 17 2016 6:03pm

So i now have to the data analysis. I calibrate my engines computer against a cat eye trip computer -everything is spot on, speeds distance maximum speed - trip.

On the next trip -

I will use a multi meter to check the initial battery voltage, and check the voltage on the engine computer to see if they match up.

Also i get the watt hours used, maximum minimum voltages.

I am guessing we should be looking at 3500mah on these GA panasonics?
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LyonNightroad   100 W

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Re: New alleged Panasonic battery failed to deliver in road

Post by LyonNightroad » Sep 17 2016 11:18pm

Just cut it open please. Post pics. I am dealing with one of their suppliers so I am curious.

This kind of stuff scares me away from thoughts of reselling.

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Re: New alleged Panasonic battery failed to deliver in road

Post by ScooterMan101 » Sep 18 2016 12:20am

Yes cut off the Shrink Wrap,
After testing the cells/pack , a few times to get good recordings of what they are really putting out.

it is possible for a Mfg, or rather in the case of batteries, for the business that welds the cells together/adds a BMS/Shrink Wraps it,
to use some bogus cells, and then sell it to an unsuspecting Vendor , like the one you bought your pack from.
How would the vendor really know ? , they just get stacks of shrink wrapped battery packs, and , packs in cases, and have to hope the people overseas
are selling, them, what they are supposed to .

Even if the cells look legit, they still could be counterfeits if the performance numbers do not add up.

We do want to see pictures .

Your experience is another reason , I am waiting for serviceable packs, ( cells in plastic holders for what ever Series and Parallel configuration you want, plastic holders that can be taken apart to change and / or inspect any of cells, and the BMS )




LyonNightroad wrote:Just cut it open please. Post pics. I am dealing with one of their suppliers so I am curious.

This kind of stuff scares me away from thoughts of reselling.
My first conversion ... Sold

viewtopic.php?f=3&t=71378&p=1077497&hil ... 1#p1077497

It's 2018 already, ( now 2019 ) lets get some real , improved e-bike / e-velomobile / e-motorcycle designs .

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Re: New alleged Panasonic battery failed to deliver in road

Post by tomjasz » Sep 18 2016 1:42am

Sadly scumbuckets le fastech sell counterfeit shrink wrap for 18650. They made them harder to find but they are still available. I happy there was no vendor mentioned but some of the top known resellers here are reliable. But those that are not actually doing the builds and testing could conceivably be taken too. Not likely, but shit happens.

Heck Bafand delivered all new bbs02 versions and told no one. Not even their purported largest reseller. Goofy business this.
Thanks Justin_le we're here thanks to you. All the best to the mods for their tireless work keeping it on an even keel.

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Re: New alleged Panasonic battery failed to deliver in road

Post by OzTrekker » Sep 18 2016 5:17am

I will attempt the mathematics.

I paid for
Fresh cells panasonic ga delivering 650-700watt hours 14AH

14 series 4 paralell.

Worst case scenario.
At the rated capacity of 3300mah = 13.2AH


My results today -
Battery consumption 555watt hours cut out at 42v.

555wh divide by 52 gives 10.5AH= the 11AH shark battery which is the inferior battery that they offer for sale.

So there are two possibility -

1 This is correct for a 14 series 3parallel panasonic battery - its missing 14 cells.
2 i have garbage chinese cells in 14s4p

The easiest solution is to "weigh" the batteries to rule out the missing cells in the first instance.
There will be a weight difference in the batteries of approximately 672grams between both batteries - given that the battery cases are identical weight.

The next step is then to test and remove an individual cell - it should produce - 3300-3500 MAH -

This is far as I have got on with my battery testing.

I suppose, if you didn't know anything about ebikes and batteries they could do you easily.

I am sure it will all work out, its just the head ache and the time it costs myself and our community having to deal with these problems.

I have dealt with many bike people internationally, from Amsterdam waterloepin market, to Spain to china to hong kong to Australia -in my hobby.

I have met a few that I truly respect. There are others that are simply out to rip yah.

Its a fun hobby but its this sort of testing that slows me down. I should be wheel building ATM not having to test under performing batteries.

When I found my lipo supplier, Day 1, tested it, it was amazing - i was smiling for 1 week and super productive into my building.

This time around I am dismayed. I was looking forward to having a ride on 700wh of new panasonic ga.

I ran out of battery on what is an easy run on my 15AH lipo - that made me depressed about this purchase

I pedaled a dead ebike home for the first time - with a battery consumption of only 555wh. It was a bad day for me.

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Re: New alleged Panasonic battery failed to deliver in road

Post by Punx0r » Sep 18 2016 6:57am

42V/14 cells is 3.0V per cell. You need to discharge to 2.5VPC to get full capacity. That's also resting voltage, not voltage under load. Also, you don't mention what rate the pack was discharged at, higher rate will return less energy. This is especially true of high energy density cells like the ones you have.

In short, you can only expect the capacity stated on the data sheet when the cells are discharged in the exactly the same manner as specified on the datasheet!

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Re: New alleged Panasonic battery failed to deliver in road

Post by OzTrekker » Sep 18 2016 7:52am

Its missing allot of range - the 15ah lipo did 47km on one charge on this bike - this new battery did under 25km range.

I dont think discharge rates can account for this gap? I was also 200m speed testing with the lipo giving it full throttle to 58km. So something has gone wrong somewhere.

And if i open up this box i would be very surprised to see 14s4p new panasonic ga looking back at me.


It appears to be missing over three amp hours - how can discharge rates account for that much.

15amp is 35km range in my experience.

I have a cruise control so i can set that too whatever discharge rate i want. I also have a 40km cycle way straight and flat.

I can do a battery maximum efficiency test based on the data above.

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Re: New alleged Panasonic battery failed to deliver in road

Post by Apex » Sep 18 2016 9:49am

Dang, I was thinking about purchasing the 52v 14mah triangle pack with the ga cells this coming week for a cyclone mid drive I'm building.
I guess I will keep an eye on this thread to see what you figure out.
I'm new to electric bikes, I'm from the ICE side of the hobby. You no doubt know more than me here, but I know that pulling nominal current vs maximum current has an impact on real world capacity. Could this be a contributing factor?
[EDIT] I see that question was just asked, doh!

I hope you get this sorted out, and that no foul play was incolved.

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Re: New alleged Panasonic battery failed to deliver in road

Post by Apex » Sep 18 2016 10:34am

What charger are you using to charge the pack?
The 52v 300 watt charger that they offer has the ability to charge at 100% or at 80% capacity. If your using that charger set at 80% then that could give you the results you are seeing.

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Re: New alleged Panasonic battery failed to deliver in road

Post by e-beach » Sep 18 2016 10:42am

This NCR18650GA cell has a nominal rating of 3.6v not 3.7. So 3.6v * 14 = 50.4v not 52v. Although, by your personal experience it dose seem like your range is more limited then it should be.

The charged voltage if this cell is 4.2v so 4.2 * 14 = 58.8. Are you charging the pack to 58.8v before riding? If you are only charging to 52v your pack may be out of balance.

It is also you have one or more bad cells in that pack. The only way to know is to ride the bike to low voltage cutoff (or very close to lvc) and meter the voltage of the cells. If your lvc is 42v then the cells should all be 3v.

Are you using a new bms that came with the battery? If so, can you test the parallel sets of cells via the bms wiring?

Edit: Also note that the specs on these cells discharge to 2.5v per cell. 2.5v * 14 = 35v. A lower voltage then you stated as lvc.

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Re: New alleged Panasonic battery failed to deliver in road

Post by OzTrekker » Sep 18 2016 11:58am

Battery Test 3.

Next ride experiment - set cut off voltage at 35v

So the discharge rate of 4 amps per cell is what we see on the chart?

Now the cycle way i have is 100km long uninterrupted straight and flat.

My questions.

Fully charged battery -

Go to the cycleway on a windless mid week day.

throttle up to 16.38amps and set the cruise control.
Let the battery run flat.

Take watt hour reading -
I will then attach a sticker to the pack.
Battery cycle number - 3
Watt hours-?
Amps drawn continuos - 16.38
Weight -
Distance -

How do you feel about this experiment?

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Re: New alleged Panasonic battery failed to deliver in road

Post by spinningmagnets » Sep 18 2016 12:08pm

I was thinking about purchasing the 52v 14mah triangle pack with the ga
The GA cell is rated for 10A peaks if I recall correctly. At 3500-mAh per cell, a 14-Ah pack is 4P, so it "should be" capable of 40A peaks.

I would not recommend that for a Cyclone. This is the battery I have for my BBSHD, and it works quite well at 30A peaks. The Cyclone is a much larger motor, so the weight and size are only a reasonable choice if you can supply it with 50A or so to really use it's full capability. (also, at 50A you really need to re-enforce the stock brackets, to avoid excessive flex, maybe add a chain-guide too?)

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nutnspecial   1.21 GW

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Re: New alleged Panasonic battery failed to deliver in road

Post by nutnspecial » Sep 18 2016 12:17pm

Good point SM. You'll never get full capacity (or cycles) out of any battery if not running at least spec. . . and generally 1/2 or less than spec with continuous and peak discharges to reach rated cycles.
How do you feel about this experiment?
That sounds good guy. Yep, as these guys are saying (along with some good tips) you'll have to make a full charge and full discharge @ draws within cell spec, to test spec'd capacity of pack.

Weight and wind and elevation and etc don't matter if you're doing a watthour reading though right? You just want to know if it has 14ah as stated.

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Re: New alleged Panasonic battery failed to deliver in road

Post by Jon NCal » Sep 18 2016 12:26pm

OzTrekker wrote:Battery Test 3.

Next ride experiment - set cut off voltage at 35v

So the discharge rate of 4 amps per cell is what we see on the chart?

Now the cycle way i have is 100km long uninterrupted straight and flat.

My questions.

Fully charged battery -

Go to the cycleway on a windless mid week day.

throttle up to 16.38amps and set the cruise control.
Let the battery run flat.

Take watt hour reading -
I will then attach a sticker to the pack.
Battery cycle number - 3
Watt hours-?
Amps drawn continuos - 16.38
Weight -
Distance -

How do you feel about this experiment?
You don't need to run it down that low of a voltage. Just look at the graph for your discharge curve, ie 4A and see when that line crosses the 3.0V line. Then look down and see how many mah it is supposed to be. Looks between 3000 and 3100mah. Also note that 25 deg. C is the test condition, will have lower capacity at lower temps.

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Re: New alleged Panasonic battery failed to deliver in road

Post by Apex » Sep 18 2016 12:36pm

spinningmagnets wrote:
I was thinking about purchasing the 52v 14mah triangle pack with the ga
The GA cell is rated for 10A peaks if I recall correctly. At 3500-mAh per cell, a 14-Ah pack is 4P, so it "should be" capable of 40A peaks.
The supplier (which shall not be named here) claims this pack is easily capable of 50 amps without getting warm, and can handle 70 amp peak. Is this being too optimistic?

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Re: New alleged Panasonic battery failed to deliver in road

Post by OzTrekker » Sep 18 2016 2:44pm

Etrike, the charts suggest that they do lose allot of capacity in the first 50 charges.

So a repeat of the field testing would give us real results.

So i can track the capacity of the battery. So i will place a simple log sticker on the battery and pen it in over time.

3 cycle
50 cycle
100cycle
200cycle
300cycle
400cycle
500cycle

When i have road tested bikes in holland the batteries had the watt hours stamped on the plastic case.

So you make the good point, thats why i will do the test now so there can be no excuses.

Sellers can try to rip you with - these batteries deteriorate fast etc...Its your riding style effecting the performance....not the fact that the battery is questionable.

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Re: New alleged Panasonic battery failed to deliver in road

Post by tomjasz » Sep 18 2016 2:59pm

Apex wrote:What charger are you using to charge the pack?
The 52v 300 watt charger that they offer has the ability to charge at 100% or at 80% capacity. If your using that charger set at 80% then that could give you the results you are seeing.
One of the worst chargers out there. It's on revision 3 or 4. Lots of posts about problems and plenty of returns too. Look at their forum. I have two of the chargers. One without a working display the other with a dead fan. The warranty from other vendors can be as much as a year. Mine from a China seller was replaced after 9 months. No questions except to confirm the shipping address. Theirs, 30-90 days depending on the mood, or how much you've spent as a customer. They also call out the Satiator as a waste of money and claim lots of returns, yet I never saw a single Satiator return in months of answering emails. $300 for a charger is painful, but when it just works and will do anything from charging my 12v SLA for my battery welder and also my 24, 36, 48 and 52v 18650 packs at any level I choose, it's suddenly doing what 5 X $99 plus shipping in chargers can't do nearly as well.

Get a Satiator and be done wondering. It'll pay for itself, oh and it comes with support and complete documentation. None of the"we ask you to do your own research.
Thanks Justin_le we're here thanks to you. All the best to the mods for their tireless work keeping it on an even keel.

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Re: New alleged Panasonic battery failed to deliver in road

Post by Green Machine » Sep 18 2016 3:42pm

As for the main issue the OP is having about getting only 11ah in the 14ah pack i think there is an easy explanation. The OP has his lvc on his controller set to 42v..... he is not running the pack to empty which is around 38v.

you need to run your pack to empty to get its full range..... the easy way to do this is turn off the low voltage cut off (lvc) on your kit and run the battery until it shuts off (the bms shuts down at around 36-38v) ....as you get really close to 36v the pack loses a lot of its power but it will still get you home and is still safe to run even if it feels like its limping.

Because of voltage sag your pack might cut off while climbing a hill before it gets drained all the way.... if this happens just cycle the power on and off and it should come back on...and its safe to keep going after doing this.

You do not want to try to run maximum amps when close to low voltage cut off...that is how you can get the maximum range out of an ebike battery pack. You want to keep the load low as you approach lvc.

Run the battery until the battery itself shuts down when it is empty.... the battery has a smart bms and knows when to do this.

If you want to be completely safe you can take a multmeter with you when doing this test and as long as the pack voltage is over 38v you are safe. The bms should never allow the pack to fall down under this level but its possible for a bms to fail which is a good reason for redundancy (when you are done with this test you can set your controller to 38v low voltage cut off as a redundancy in the rare case the bms fails)

Also i recommend that if you do run your pack to low voltage cut off that you charge it after your ride and do not store it empty....

But you cant say you are not getting the ah you paid for when you are forcing the pack to shut down at 42v....thats a quarter tank of "gas" still left in your tank and you should use it.
Last edited by Green Machine on Sep 18 2016 4:52pm, edited 2 times in total.

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Re: New alleged Panasonic battery failed to deliver in road

Post by Apex » Sep 18 2016 3:45pm

That would explain it, Green Machine.
Once I looked at other battery pack info, I saw that most ga cell packs include that claim. Thanks for straightening that out.
I'll pm you about a pack for my cyclone kit.

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Re: New alleged Panasonic battery failed to deliver in road

Post by Green Machine » Sep 18 2016 4:46pm

The vendor is not confirmed . I have pmed the OP and have not heard back yet...but i respect that he has kept the vendors name private.

I dont know if its one of our packs and cant say for sure if it is. But i am familiar with this type of pack and someone quoted something from one of my adds earlier.

My post got too long so i cut the post in half and saved what i wrote regarding heat for later post to keep things clear.

So here is what i wrote:

Apex wrote:
"easily capable of 50 amps without getting warm
That's not optimistic, it is a flat out lie."

That sounds like my writing and i take responsibility and apologize for this :)

Yes this is my mistake and my fault for copying over information from other packs when writing adds and not proofreading close enough and i missed that line in one of our triange GA adds. But i did not deliberately mean to deceive anyone and will do a better job of proofreading the adds.

That line was intended for the 25r triangle which is what i used as a model when writing the GA add. ..which is a different beast. I have a lot of respect for the 25r cell and say often that its hard to get a 25r pack warm at reasonable performance levels (under 50amps).

The GA cell is NCR chemistry, which is very similar to the NCRB (both made by Panasonic).... and these particular chemistries like to run warm and even hot. Its not a bad thing...its just the nature of the chemistry.

Granted the GA runs a lot cooler than the NCRB but it still runs warm and sometimes hot depending on how hard you push it....but dont let the heat scare you..... it also makes a good hand warmer on cold days when out riding in the winter :).

The 25r is INR chemistry which is more well suited for high amperage and its true that its hard to get a 25r pack warm even at 50 amps in any pack over 15ah or so....and when i write the line about not even get warm its meant for the 25r.

So why not make all our packs for INR chemistry? INR chemistry do not have the same energy density...for example a 25r cell is 2500 mah and the a GA cell is 3500 mah. If you dont need high amperage (you are running a typcial bbshd or bbs02 kit) you really dont need 25r cells.

We love that we are able to fit 700 watt hours in that tiny shark pack.... to do that we must use ncr chemistry cells. A shark pack is not as intersting at 10ah (500 watt hours) which is all we would get if we make it from 25r cells...and it would cost about the same.

well unfortunately we live in a time where you must choose between energy density and ultra high performance.... and oh yes also price. I always say you can have long range, or small and lightweight or high power, or cheap (but you cant have all 4...in fact you can probably only pick 2)

The GA is my favorite cell right now for most ebikers because it has no problem putting out enough power for a 30amp system like the BBSHD without getting too hot (hot enough to trigger the bms shutdown). In the GA you get the ulitimate in power density (3500mah per cell) In my opninon the GA cell is optimal for hard case sharks etc and a 30 amp system like the bbshd.

All our packs big and small have temperature sensing built into the bms...most of them have 2 separate thermostats for different parts of the battery. They shut down if they get too hot to a point where your pack could get damaged.

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Re: New alleged Panasonic battery failed to deliver in road

Post by OzTrekker » Sep 18 2016 7:17pm

My log shows

Max Voltage 59.9
Min voltage 7.2v

Battery consumption 555.592 watt hour.

Should I have had a BMS kick in to protect the battery?



Should i add a thermometer to the test?

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Re: New alleged Panasonic battery failed to deliver in road

Post by e-beach » Sep 18 2016 8:03pm

OzTrekker wrote:My log shows
Max Voltage 59.9
Min voltage 7.2v
Battery consumption 555.592 watt hour.
Should I have had a BMS kick in to protect the battery?
Should i add a thermometer to the test?
59.9v is a very high state of charge for 18650 batteries.

Industry best practices have shown that cells that are somewhat undercharged and never fully discharged will last longest.

4.2v x 14 = 58.8v. This is the voltage your 14s pack should be charged to.
But, for the pack to charge to 59.9 shows that the cells can a high voltage. Sounds like the cells are good.

Did you battery pack not come with a BMS?
A properly functioning bms will stop the over-charge and over-discharge of you cells depending on how it is configured at the factory. It will also balance your cells.

How did you get the 555.592 wh and 7.2v readings?

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Re: New alleged Panasonic battery failed to deliver in road

Post by Samd » Sep 18 2016 9:06pm

Interesting. Sub'd.
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Re: New alleged Panasonic battery failed to deliver in road

Post by amberwolf » Sep 18 2016 9:23pm

Is that 59.9v at the battery inside the packaging, or at the wires where they connect to the charger (outside the BMS)?

If the latter, then the battery (cells) may never have even seen that high a voltage, it might just be what the charger outputs when the BMS disconnects the pack at HVC to protect the cells.

You'd need to measure at the actual main interior + and - wires, on the cell-side of the BMS, to find out what those actually are (and also measure the individual cell group voltages at the BMS connector to see if they're balanced, if you want to know that).



Regarding actual Wh / Ah provided by the pack, you'd need to use a wattmeter to measure that. Wh can't accurately be calculated by multiplying a static voltage with the Ah that's measured; it depends on actual voltages from HVC all the way down to LVC and any sag from load.


For some possible info about vaguely similar packs to this one, you can go here:
https://endless-sphere.com/forums/viewt ... 14&t=81108
though your pack has different cells and possibly a different BMS.

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