KS18l won´t charge past 81 %

[Christopher Heijkers]

Hi there, i have a Problem, my brand new ks 18L won´t charge past 81 %  the voltage of both the pack´s combined is 80 Volt. I tested 2 independet chargers without any luck. There is a guy on youtube who has the same problem, but no solution to be found. Is there a update ?

[mrelwood]

Not charging to 100% is a clear indicator of either a bad charger or a failed battery cell group. Several people have had it happen, and the search phrase ”not charging past” should find the discussions at the forum.

If the charger is bad, it’s just not giving enough voltage. But since you already tried two different chargers, I’m afraid...

The battery likely has a dead cell group. The BMS cuts off the charge if any of the cell groups reach 4.25-4.3V. If one group is dead, the other groups try go higher than what the BMS allows, and the charging stops. One cell group short of 84.2V is exactly 80.0V. Such wheel has lost a lot of range and power, so be careful when accelerating or hitting bumps and inclines!

If the wheel is new, it is a clear warranty situation; the wheel you received is faulty. It may have been sitting with an empty battery for too long.

I’d recommend demanding a new unit.

Edited April 16, 2020 by mrelwood

[Christopher Heijkers]

I think so aswell, but i hope it´s just an unbalanced pack. because it charges after a little ride to drain the battery a tiny amount to 81.35 Volt. 

 

Since i got my wheel yesterday i charged it to 95 % and drove it to 20 % then i charged it to 77 % then drove back home

 

perhaps the BMS didn´t had the time to Balance the Pack so there is some difference between the cells and an overly protectiv BMS cut´s the charge current bevore complete balancing can occur? 

 

My  tactic is to discharge it slightly and then recharge it in order to bumb up the Voltage on the pack to force it to balance since these "dumb" BMS Systems just balance at the end in the trickle charge phase ( i think ?)

 

Warranty is a very tricky thing in germany, the local dealers hide behind rules and just say the can send in the Unit for repair but that could take as long as 6 - 12 weeks  

 

The only thing that i can do to be sure is to take the unit apart and measure each cell group, that isn´t a problem since i am an electrician. 

 

But i think that would void my warranty  or  does it ? (Vsauce music playing ^^ <)

[Chriull]

1 hour ago, Christopher Heijkers said:

I think so aswell, but i hope it´s just an unbalanced pack. because it charges after a little ride to drain the battery a tiny amount to 81.35 Volt. 

 

1 hour ago, Christopher Heijkers said:

Since i got my wheel yesterday i charged it to 95 % and drove it to 20 % then i charged it to 77 % then drove back home

 

perhaps the BMS didn´t had the time to Balance the Pack so there is some difference between the cells and an overly protectiv BMS cut´s the charge current bevore complete balancing can occur? 

One does not want a new unvalanced pack! It will not last long. Balancing works a little bit, but it seems proper cell matching is the key for a good pack.

https://batteryuniversity.com/learn/article/bu_803a_cell_mismatch_balancing

From experience of the reports here such not fully charging packs almost ever reveal bad cells.

Mostly/often it's only one pack with bad cells - the other parallel pack is in good condition!

1 hour ago, Christopher Heijkers said:

 

My  tactic is to discharge it slightly and then recharge it in order to bumb up the Voltage on the pack to force it to balance since these "dumb" BMS Systems just balance at the end in the trickle charge phase ( i think ?)

They balance (mostly) while stage 2:

So slight discharge (~10-15%) and repeating stage 2 is afaik the perfect way to force balancing.

1 hour ago, Christopher Heijkers said:

Warranty is a very tricky thing in germany, the local dealers hide behind rules and just say the can send in the Unit for repair but that could take as long as 6 - 12 weeks  

The seller can choose to repair 12 weeks?

For non functioning equipment on arrival there is no chance for the customer to return/conversion?

1 hour ago, Christopher Heijkers said:

The only thing that i can do to be sure is to take the unit apart and measure each cell group, that isn´t a problem since i am an electrician. 

I'd assume one of both packs had dead cells. So if you charge both individually one should reach perfect 84V.

If you try this and this is the outcome you know quite sure that you can dump the one pack only charging to ~80%. So one can cut it open and measure, as its not usable anymore. Afair KS18(X)L BMS have at one corner a 21 pin plug hidden under the plastic wrap which offers connection to each cell group! So a small cut us sufficient for measuring.

1 hour ago, Christopher Heijkers said:

 

But i think that would void my warranty  or  does it ? (Vsauce music playing ^^ <)

Yes it will. But i'm not sure about just opening and "looking"?

Best to proceed in accordance with the seller - or supported by an advocate

[mrelwood]

If you are not going to use the warranty for this, you wouldn’t really need it for anything else either. The battery packs are easily the most expensive single part of the EUC.

The balancing current at least on KS wheels is very tiny. It has been questioned wether it is sufficient to properly even keep the balance of a healthy pack under normal use. If the charge stops at around 80V, I don’t think there is a chance of getting the cells back on track by BMS balancing.

Remember that the wheel doesn’t know how low the individual cell group voltages reach under use. If the highest group stops the charge at 4.3V yet the pack total is at 84V, some of the groups probably never get above 3.7V. When the pack is at 20%, the lowest groups are probably below 2.6V. I think that’s when the almost dead group finally died.

[Christopher Heijkers]

"The seller can choose to repair 12 weeks?

For non functioning equipment on arrival there is no chance for the customer to return/conversion?"

 

The dealers in germany had to be granted 2 repair run´s when these are both unsucessful you can return the bike but you have to pay for the usage you will not be fully refunded.

 

and you have to give the dealer up to 12 weeks for 1 try. 

 

besides Warranty couldn´t you just help the bms by opening the battery and manually discharging the cells which are to high ?

 

And you have to pay shipping fees to the dealer which is up to 20 Euro.

[Chriull]

2 minutes ago, Christopher Heijkers said:

The dealers in germany had to be granted 2 repair run´s when these are both unsucessful you can return the bike but you have to pay for the usage you will not be fully refunded.

 

and you have to give the dealer up to 12 weeks for 1 try. 

And "online customer protection"? In austria we have a "fernangabegesetz?" which allows returns within 14 days.

2 minutes ago, Christopher Heijkers said:

besides Warranty couldn´t you just help the bms by opening the battery and manually discharging the cells which are to high ?

The cells charging to high are not the problem - they are the ones which are ok. The cells not charging anymore (dead cells) are the ones causing the problem. One cannot make them working again - only replacement would he possible.

[Christopher Heijkers]

Yes you are right about the online customer protection, i used it so that´s unfortunatly out of the way.

 

I purchased the wheel yesterday and it arrived with about 30 % charge. It is the newest Version in matt black, is it possible to be dead on arrival ?  or should i just give the BMS more cycle to balance the cells it´s now charging to 81.6 Volt after 3 little discharge and charge cycles ( around 10 - 20 % ) should i just watch the charge cutoff voltage carefully ? if it creeps up to 84 volt then the pack is good or do you think i have to send it in ?

[Chriull]

1 hour ago, Christopher Heijkers said:

or should i just give the BMS more cycle to balance the cells it´s now charging to 81.6 Volt after 3 little discharge and charge cycles ( around 10 - 20 % ) should i just watch the charge cutoff voltage carefully ? if it creeps up to 84 volt then the pack is good or do you think i have to send it in ?

I would personally send it in. Just would try to search easy problem solution before in accordance with the seller like described above looking if only one pack is bad. So the reseller can just send a new pack... But of course only possible if the seller cooperates.

[Christopher Heijkers]

I came to the conclusion, that like you all said the 1 of the 20 battery cells (2 in fact ) must be dead and that they are not charging along with the others.

It always cut´s the charge current at 81,48 Volt which translates to 4,28 Volt in the remaining cells i think thats the cutoff voltage of 1 the Battery pack BMS if you add the tiny voltage drop across the discharge cut mosfets you are pretty much spot on to 19 x 4,25.

 

what a bummer, i bought this wheel as a method of driving around and having a little bit of fun during these times and now

 

I will bring it back to my local dealer, but he already said, that he will ship it to the importer and he will verify the problem and then we have to wait for a replacement battery i think. 7

Here in germany the local dealers are worth nothing, they only can ship it to the manufacturer.

 

I anticipate at least 6 weeks. Ou you can´t imagine how angry i am. 

 

Or would you demand a refund as described in the "fernabsatzgesetzt" cause i read a little and you can test the product and you can use it for a limited time and still get fully compansated.

I love the KS18l but the battery problem is, as far as i am concerned an absolut no go for a device costing as much as a used car

[mrelwood]

The way I see it, your options are:

- Return for warranty repair, and possibly be 3 months without a wheel.

- Return for full refund.

- Ask the seller if you can open up the wheel and inspect which battery pack is faulty. Remove faulty pack, take the faulty pack to the seller, ride carefully with one pack only as you wait for the new pack. Charge/discharge the packs to the exact same voltage, open up the wheel again, install new pack.

The last option requires quite a lot of work for a new product, and might not be ok with the seller. But it would keep you riding.

If you can get another wheel faster than in 3 months from somewhere else, I would definitely return the wheel for full refund ASAP.

[Chriull]

1 hour ago, Christopher Heijkers said:

I will bring it back to my local dealer, but he already said, that he will ship it to the importer and he will verify the problem and then we have to wait for a replacement battery i think. 7

You can think about naming the reseller here - just as "warning" for other members. (For fairness with a note to the reseller so he can make here his own statement)

Identifying a bad battery pack and replacing it is no miracle. And for just forwarding parcels and writing receipts the markup is not justified.

1 hour ago, Christopher Heijkers said:

Here in germany the local dealers are worth nothing, they only can ship it to the manufacturer.

Not all, afaik.

Biggest prob is imho that one needs a certain size/turnover so some stock with replacement parts can be financed.

[meepmeepmayer]

Return it or demand a replacement, now. This (a faulty battery pack) is a warranty situation if there ever was a warranty situation.

[Sebrios]

Maybe its not the case, and you are aware of this...

But...

With the app you are checking the battery level, do you have it set at 84V?

Else, you will get funny numbers...

Just saying... Maaayyyybbeee there's the problem, and you don't need to do much

[Rywokast]

i would not do anything, i wouldnt open it then you might be blamed.. this is absolutely ludicrous that they would even consider not returning this.. im not sure about where you live but they have to have some sort of consumer protection policy in the law.. i would refuse anyone to work on it on my dime or my time, they pay the return shipping and they ship out a brand new unit, on their dime.. if they refused i would take pictures and report them and then do a chargeback on my credit card, using the conversation with them as proof of fault.. you shouldnt have to wait more than one day thats so ridiculous, and i absolutely wouldnt accept this or ride it as it can be dangerous

Edited April 5, 2020 by Rywokast

[.....]

I'm with RywoKast on this one. Little scratches or blemishes are no big deal, but you are talking the LIFE BLOOD of the motor. More than anything else, the batteries are UBER IMPORTANT! Not to mention, they are VERY expensive. From the moment they are made, they start to age. When you get a wheel, the battery is the big ticket item that needs the most care and maintenance. If i buy a NEW car, I EXPECT the engine to run on ALL cylinders. When I go to buy a new wheel, it damn sure better be up to spec or its going RIGHT BACK! Maybe I'm spoiled here in USA, but a seller has an obligation to make sure you receive a FULLY FUNCTIONAL item. This includes issues that were only found once the item was put into use. Its unrealistic to deny a claim because its been used for a moment, as it takes using it, to verify its operation at all. You have to try and charge it BEFORE you can even verify it has batteries in spec, you have to ride it to see if the motor even works. As a consumer, I have visa and paypal who will side with me in an instant, should something arrive damaged. The seller always risks losing in a transaction, but they also risk profiting too. An upgraded pack for an 18xl is around $800 or so i think. This is NOT merely a flat tube or a bad led or a scuff. With the danger of overlean and cutout from poor battery performance... get another euc or pack.  If you don't trust the seller, I WOULD NOT offer to install the pack myself. You can be blamed for everything too easily. What happens when YOU repair it, but these bs cheap screw strip out, or god forbid, you find something else amiss?  Having to wait so long for a replacement or repair is rough, but I would venture that route, rather than risk using a bad pack. If you can get a refund and order an entirely new wheel in less time, I'd try that too. Best of luck, I know it hurts when crap like this happens.  Not to rub your nose in it, but my 18L has been wonderfully problem free since the day I got it. Just saying... they arent all rotten eggs. I'd imagine Kingsong doesnt make batteries, so the blame is on whoever they contract batteries from, or perhaps themselves for not having adequate presale testing. Or, just a fluke and shit happens... The current state of affairs with the virus is going to make it take longer, im afraid.

Edited April 5, 2020 by ShanesPlanet

[Christopher Heijkers]

i think you have way more expirience than me,

 

would you say, if the dealer agreed to take it back would you go for another 18l or a V10F or the ks16X ?

 

I know the v10F is inferieur but i owned a v8 back in 2018 and it still works like a charm.

 

i have to honest i am struggeling to trust kingsong after this. 

[Rywokast]

54 minutes ago, ShanesPlanet said:

I'm with RywoKast on this one. Little scratches or blemishes are no big deal, but you are talking the LIFE BLOOD of the motor. More than anything else, the batteries are UBER IMPORTANT! Not to mention, they are VERY expensive. From the moment they are made, they start to age. When you get a wheel, the battery is the big ticket item that needs the most care and maintenance. If i buy a NEW car, I EXPECT the engine to run on ALL cylinders. When I go to buy a new wheel, it damn sure better be up to spec or its going RIGHT BACK! Maybe I'm spoiled here in USA, but a seller has an obligation to make sure you receive a FULLY FUNCTIONAL item. This includes issues that were only found once the item was put into use. Its unrealistic to deny a claim because its been used for a moment, as it takes using it, to verify its operation at all. You have to try and charge it BEFORE you can even verify it has batteries in spec, you have to ride it to see if the motor even works. As a consumer, I have visa and paypal who will side with me in an instant, should something arrive damaged. The seller always risks losing in a transaction, but they also risk profiting too. An upgraded pack for an 18xl is around $800 or so i think. This is NOT merely a flat tube or a bad led or a scuff. With the danger of overlean and cutout from poor battery performance... get another euc or pack.  If you don't trust the seller, I WOULD NOT offer to install the pack myself. You can be blamed for everything too easily. What happens when YOU repair it, but these bs cheap screw strip out, or god forbid, you find something else amiss?  Having to wait so long for a replacement or repair is rough, but I would venture that route, rather than risk using a bad pack. If you can get a refund and order an entirely new wheel in less time, I'd try that too. Best of luck, I know it hurts when crap like this happens.  Not to rub your nose in it, but my 18L has been wonderfully problem free since the day I got it. Just saying... they arent all rotten eggs. I'd imagine Kingsong doesnt make batteries, so the blame is on whoever they contract batteries from, or perhaps themselves for not having adequate presale testing. Or, just a fluke and shit happens... The current state of affairs with the virus is going to make it take longer, im afraid.

KS uses LG or Sanyo, but they of course just make the cells, kingsong is responsible for making the packs, wiring and testing, bms etc.. whether it was a QC issue or happened somehow after being assembled who could know.. either way, doesnt matter, not the problem of the customer.. you bought a new product which means in perfect condition and working 100% as specified.. all the dealer has to do is send you a new one and ship that one back to KS for being faulty, or swap out the bad battery pack(s) and sell as refurbished, which i assume dealers would also not be responsible for this cost.. at least not wholly

[Rywokast]

5 minutes ago, Christopher Heijkers said:

i think you have way more expirience than me,

would you say, if the dealer agreed to take it back would you go for another 18l or a V10F or the ks16X ?

I know the v10F is inferieur but i owned a v8 back in 2018 and it still works like a charm.

i have to honest i am struggeling to trust kingsong after this. 

i would not recommend the v10f to anyone in 2020 for any reason (besides a deal too good to pass up).. its not bad, its just not good especially for the price lol... what i would recommend, out of those.. the 16X but i would definitely personally recommend the 18XL over the 16X for its higher safe top speed and looks... i cannot comment on the ride as i havent owned one, but ive been told its great.. it all depends what youre looking for in a wheel, though compared to the 18L/XL the 16X has a lot of issues.. theyve mostly been worked out by now, but still it is not quite as safe as the 18L/XL.. nimble and more torque 16X wins, safer top speed and more comfortable cruiser 18L/XL wins.. i personally love the look of the 18L and despise the look of the 16X but thats just me.. do not let this sour you, youre in the 1% of the 1% the chances of something like this happening are so minuscule that they are not even worth considering, anyone can get a dud its just bad luck.. kingsong has normally excellent QC. the v10f is underpowered, underwhelming, and overpriced

[Meserias]

Christopher Heijkers please evaluate also acquisition of Gotway Tesla V2 (1482wh version)

[Rywokast]

6 minutes ago, Meserias said:

Christopher Heijkers please evaluate also acquisition of Gotway Tesla V2 (1482wh version)

I'm thinking the reason for his selection is that's what the local dealer has.. though obviously the whole point of doing business with a local dealer is lost on whoever he bought it from as the customer service is worse than China... might as well get one from aliexpress where you have a lot more options and they're cheaper.. I'm very intrigued though always a bit wary of third party additions, but if it's legit a 1482 wh tesla would be fantastic.. that's why the tesla could never replace the acm2 to me is because if it's lacklustre battery.. same life as my 16s.. but that big a battery in that package would be very desirable and the price is good too, the tesla is a great wheel

Edited April 5, 2020 by Rywokast

[mrelwood]

 

Quote

would you say, if the dealer agreed to take it back would you go for another 18l or a V10F or the ks16X ?

I think that depending on the price, the 18(X)L is still the winner, for the reasons mentioned by @Rywokast. The 16X is a nice ride and even a bit more ergonomic than the 16X, but the difference is not too big.

Quote

i have to honest i am struggeling to trust kingsong after this. 

Perfectly understandable, but try to remember, your bad experience of a single faulty unit means very little in statistics. Dozens of good KS wheels are sold every day around the world. And the probability of getting a second faulty wheel is even smaller!

If the seller claims UP to 12 weeks of repair time, my guess is that a faulty battery is easy enough to determine that it might not end up taking anywhere near that long for them to examine and replace the pack. Just a guess though.

If you end up buying from Aliexpress, don’t get a KS from there. KS are pretty aggressive in limiting the features of wheels sold by unofficial distribution channels. Even long after purchase, since the serial number has a specific marker for that.

Edited April 5, 2020 by mrelwood

[.....]

ALL manufacturers suffer this type of thing on occasion. It's a low chance, but it happens. The KS18 series has a decent track record, but i feel your pain. When grading these wheels, you kind of have to grade them ALL on a sliding scale. We arent looking at aircraft quality here. The KS feels pretty damn refined to me, and I'm at a loss of how I would do much better for my own needs atm. I fear that what happened to you, could easily have happened to ANY euc company.  You may find it easier to have it swapped for another of the same, sometimes dealers frown upon switching out types on a return. Just a long shot, but have you reached out to Kingsong directly? They may not be equipped to 'talk' to you directly, but you never know. It sure would prove good if you got some kind of support from them. Even a response at all, could sway you into not giving up on the brand. I've heard from them directly before fora  simple 'hello' on facebook. I bet they could repair your pack in very little time, and MAY put it on the 'urgent' table.  I've a few vids on my KS18L and it really has proven to be solid. I opened it when I got it. I didnt see any big corners being cut in the design, but I also didnt see bulletproof materials. Again... sliding scale, these are ALL built to a price point and not on a massive scale.  *Agreed on aliexpress. I buy things from there a lot, but some of these wheels are speed locked by geographic location or VIN or someshit. I've heard bad things about buying from unknown sources and Ali. If my 18L exploded today, I'd replace it with an 18XL(from jason *our dealer who seems to care) and drool over what new comes later this year. Euc is a small and close knit community, this kind of helps persuade dealers to be transparent.

Edited April 5, 2020 by ShanesPlanet

[meepmeepmayer]

5 hours ago, Christopher Heijkers said:

i have to honest i am struggeling to trust kingsong after this. 

Buy the wheel you want! A bad battery pack is an extremely rare occurrence and means little other than you simply had bad luck.

[Chriull]

6 hours ago, Christopher Heijkers said:

i have to honest i am struggeling to trust kingsong after this

EUCs are no mass products and miss "perfect" QC. Although their quality and reliability improved greatly over the years. Afair @Jason McNeil stated that the most returns come /problems are directly after unpacking. After that there are not really anymore faults to be expected.

No manufacturers excluded...

So every order is a bit of a lottery - with some small chance one gets a bad product...