Charging question

[HJ]

and, since there's a BMS already attached (and I assume) working, then am I limited by the number of seriial cells?  really, what's important is the voltage of the charger right? As long as I charge to a certain voltage (67 for the euc) and don't charge too fast, right?   One issue with the 206B is that it sets for specific numbers of cells (i.e 3 cells for 12 v, 6 cells for 24 v).  I don't know that it can output at a specific 67 v.  

would this work? http://www.batterysupports.com/60v-672v-576v-5a-lithium-ion-lipo-battery-charger-16s-16x-36v-p-169.html

[Chriull]

26 minutes ago, HJ said:

I am somewhat familiar with lipo charging as I have an ebike (72v) that I charge a lot.  Just not sure of the whole '16s' thing.

16s means 16 li ion cells are in series. So the charger has to deliver 16*4,2V for charging (in the second phase, in the first phase the constant current until the cells reach this voltage)

26 minutes ago, HJ said:

 My charger (Icharger 206B) is rated to charge  up to 8 lipos in serial (the lipos I use for the bike are the standard 'brick' type 6s - 22 volt packs), but it sounds like I have packs of 16 of the 'battery' type cells.  Does it matter that this is more than 8 lipos in serial? Or is it just the  voltage going in thats important.

It just wont charge the 16s packs you have in the EUC.

Its the max voltage thats important - a charger for 8s has a too low max voltage, so the 16s packs (with normal BMS) wont even "notice" that you put the charger on...

And imho there could be quite some differences between LiPo and Li Ion cells?

[Chriull]

23 minutes ago, HJ said:

and, since there's a BMS already attached (and I assume) working, then am I limited by the number of seriial cells?  really, what's important is the voltage of the charger right? As long as I charge to a certain voltage (67 for the euc) and don't charge too fast, right?   One issue with the 206B is that it sets for specific numbers of cells (i.e 3 cells for 12 v, 6 cells for 24 v).  I don't know that it can output at a specific 67 v.  

would this work? http://www.batterysupports.com/60v-672v-576v-5a-lithium-ion-lipo-battery-charger-16s-16x-36v-p-169.html

Seems to. It has the 67,2V for 100% charge (and 57,6V and 59,2V for partial charge), CC/CV Mode. Just the 5A is a bit more then the 4A from the Kingsong fastcharger - i think i would risk this difference (but that's not a recommendation - its your decission because its your EUC )

It also seems, that you need a different connector to the EUC?

It looks similar to the modell that cranium mentioned - imho he was quite satisfied with his choice. And he described in detail how to change the max voltage and max current for his modell. Why don't you choose his way? Or maybe its the same model anyhow?

[HJ]

excuse my extreme 'newnbieness', but just making sure: these cells are li-ion and not li-poly, right?   Ive only ever used r/c type lipos in my drones and Ebikes, and was also wondering about the configuration I could use if I wanted a separate lipo external pack, 6s vs 5s.   What is he max voltage for the KS 18, 67v or slightly higher?  3 serials of a 6s lipo = 22v x 3 = 66 v,  perfect, but when I charge them the actual end voltage is more like 74v.  Would this be too much for the euc?

H

i.e would 74 v damage the motor or control board?  Conversely, a 5s 3 serial setup would probably give about (18.5 x 3 = 55.5v, but more on full charge) would be safer but doesn't seem to have enough volts

[HJ]

the reason I ask this is that while I wait for the replacement charger to be sent from KS......I WANT TO RIDE!!!!! and I've got lipos aplenty, LOL   

[Chriull]

37 minutes ago, HJ said:

excuse my extreme 'newnbieness', but just making sure: these cells are li-ion and not li-poly, right?

right.

Quote

  Ive only ever used r/c type lipos in my drones and Ebikes, and was also wondering about the configuration I could use if I wanted a separate lipo external pack, 6s vs 5s.   What is he max voltage for the KS 18, 67v or slightly higher?  3 serials of a 6s lipo = 22v x 3 = 66 v,  perfect, but when I charge them the actual end voltage is more like 74v.  Would this be too much for the euc?

H

i.e would 74 v damage the motor or control board?  Conversely, a 5s 3 serial setup would probably give about (18.5 x 3 = 55.5v, but more on full charge) would be safer but doesn't seem to have enough volts

The board is at least designed for a voltage of 67,2V (16*4,2V). It should withstand maybe a bit more (Voltage generated from the motor while regenerative breaking) - but i assume noone but the KingSong Engineers can give you an answer to this...

You are really thinking of plugging a Lipo with 66V to 74V externally to your EUC which is actually charged to about 60V? I am quite shocked and hope this is just some kind of misunderstanding... But imho we should and can stop talking about batteries - you should have a much easier solution to your problem:

30 minutes ago, HJ said:

the reason I ask this is that while I wait for the replacement charger to be sent from KS......I WANT TO RIDE!!!!! and I've got lipos aplenty, LOL   

Then why don't you ride? The battery packs are quite charged - you said you still have 8 out of 10 bars. And after riding your charger should be able to charge them again to 60V which is still a bit above nominal voltage. Should be something like a 50-60% charge. So from the 1360Wh pack you will have more than enough range again...

 

 

[HJ]

13 minutes ago, Chriull said:

right.

The board is at least designed for a voltage of 67,2V (16*4,2V). It should withstand maybe a bit more (Voltage generated from the motor while regenerative breaking) - but i assume noone but the KingSong Engineers can give you an answer to this...

You are really thinking of plugging a Lipo with 66V to 74V externally to your EUC which is actually charged to about 60V? I am quite shocked and hope this is just some kind of misunderstanding... But imho we should and can stop talking about batteries - you should have a much easier solution to your problem:

Then why don't you ride? The battery packs are quite charged - you said you still have 8 out of 10 bars. And after riding your charger should be able to charge them again to 60V which is still a bit above nominal voltage. Should be something like a 50-60% charge. So from the 1360Wh pack you will have more than enough range again...

 

 

I am, and I do, but the charge is going down.  now at 4 bars, and only charging up to about 59.2v.  I'm afraid that if I continue I'll have a cut-off.

[Chriull]

With 8 cells in parallel working for you i would not worry too much - imho should still be "safer" as all the 100-300Wh EUC riders.

And by this you have maybe the unique chance experience how your wheel shows you low bat status - which should be quite safe, from whats reported about Kingsong around here...

Maybe some KS (way too much) Wh  riders can give you some first hand reports about what to expect.

Or just use this time to perfect your skills, get one with the wheel and postbone pushing your wheel to the absolute limits once you get the replacement charger ?

[HJ]

....good advice.

[esaj]

2 hours ago, HJ said:

excuse my extreme 'newnbieness', but just making sure: these cells are li-ion and not li-poly, right?   Ive only ever used r/c type lipos in my drones and Ebikes, and was also wondering about the configuration I could use if I wanted a separate lipo external pack, 6s vs 5s.   What is he max voltage for the KS 18, 67v or slightly higher?  3 serials of a 6s lipo = 22v x 3 = 66 v,  perfect, but when I charge them the actual end voltage is more like 74v.  Would this be too much for the euc?

H

i.e would 74 v damage the motor or control board?  Conversely, a 5s 3 serial setup would probably give about (18.5 x 3 = 55.5v, but more on full charge) would be safer but doesn't seem to have enough volts

Take this with a big grain of salt, as I'm no expert, and could be wrong, but here's what I know (means what I have read) about this:

LiPo or lithium-polymer was "originally" meant to mean the solid state lithium-batteries, but as they haven't really got them working still, what we currently know as "lithium-polymer" is basically your "standard" Li-Ion chemistries (of which there are varying kind) used inside pouch-type containers instead of metal casings. The good side is much lower internal resistance (can be charged & discharged with higher amperage / can give out much higher current without overheating), the bad side is that the pouches are not nearly as resistant as the metal casings, and can rupture much more easily (either due to puncture or because they swell somewhat when they have high charge). 

Different chemistries have somewhat different characteristics, but most of them have a nominal voltage between 3.6V and 3.7V per cell (the exceptions are LiFePo4 and Li-titanate, which have much lower voltages, and cannot be charged with similar voltages as the others). You see both 3.6 and 3.7V being used depending where you look, even for same chemistries. Maximum voltage (again for others than LiFePo and Li-titanate) is usually reported as 4.2V per cell, and for some chemistries slightly higher (I think it was LiNiMnCo/NMC that can go all the way up to 4.35V). It's (usually) the maximum voltage to which the batteries are loaded during charging, so the total voltage depends on how many cells there are in series. Most wheels use 16S (16-in-series) -packs (Ninebot uses 15S), of which there can be multiple in parallel, sometimes more than one series of 16 cells are wrapped inside a single pack. So using the "typical", "safe" value of 4.2V per cell with 16S you get

4.2V/cell * 16 cells = 67.2V

That's the maximum charging voltage, although some charges can put out slightly higher voltages (probably to overcome the 0.25...0.7V voltage drop caused by a reverse polarity protection diode in the BMS). Like Chriull said, the charging happens in two phases: first a constant current -phase, where the charger keeps the current at a set value (like 4A for example), until the charging voltage reaches that maximum value above (67.2V). After this, the rest of the charge is constant voltage -phase, until the charging current dies out (drops to 0) when the batteries have reached the full voltage. Always charging the packs to full voltage does stress them at least somewhat, but on the other hand, most BMSs used in the wheels seem handle the balancing only near the full voltage(?), so charging all the way to full at least now and then is probably recommendable, even if it does (slightly) reduce the maximum charge/discharge -cycles you get out of a pack before it "wears out" (basically it'll start dropping in capacity slowly, ie. it won't charge to as "full" as when new).

74V would definitely be too high. Li-ion does not "like" being overcharged, and can in the worst case vent, catch fire or even explode if you really try to force it. However, "undercharging" it with 60V or so should be just fine, actually it should prolong your battery pack lifetime (as long as you get the cells balanced every now and then by doing a full charge). Li-ion does not suffer from the so-called "memory effect" some other battery types (NiMH, NiCD?) have, and "random" charging is just fine, as well as charging it even when it's not completely empty.

[HJ]

well, there it is.  Appreciate your thoroughness there.I have a lot of experience with the lipo packs, none with the li-ion cells.  This is mostly just an exercise in what can be done theoretically.  I value my euc too much to experiment. I'll just ride at 59v slow and careful like until I get this charging issue resolved.

Thanks,

H

[HJ]

 This is all been very informative. Thanks a lot. One last question: if I wanted to bypass my charging port altogether, and wanted to charge my batteries directly, with that be a hard thing to do using a charger then actually gave me 67 V? That is, all I need to do is make a connection Between the battery terminals (Being careful with polarity), paralleling the packs or individual, and the Charger's two active pins, bypassing the charging port.  Just in case, when I get my new charger, I still have an issue  that might be related to the port Itself.  

[esaj]

1 hour ago, HJ said:

 This is all been very informative. Thanks a lot. One last question: if I wanted to bypass my charging port altogether, and wanted to charge my batteries directly, with that be a hard thing to do using a charger then actually gave me 67 V? That is, all I need to do is make a connection Between the battery terminals (Being careful with polarity), paralleling the packs or individual, and the Charger's two active pins, bypassing the charging port.  Just in case, when I get my new charger, I still have an issue  that might be related to the port Itself.  

Charging directly by wires is a possibility, but not very safe (accidental short circuit) or convenient in the longer run (if you have the wires dangling around inside/outside the wheel). Charging packs separately is also possible, but you need make sure that they're closely at the same voltage before attaching them back together in parallel. 

If the charging port/connector is faulty, you could replace the port with another (the "typically used" charging port/charger connector is male/female GX16-3 -pair, Ninebots use some Lemo-plugs, but don't know the specific type code). The port/connectors themselves are just "means" to attach the charger to the charging side of the BMS, so you could use some other type of connector-pair too, anything that can withstand high enough current and is rated for at least 70V should work (of course should you use some other connector, take into consideration how you're going to attach it to the shell, how to protect the connector from taking in water while riding etc., common sense takes you a long way ).

 

[HJ]

Ok, so on a hunch the this charger/plug was Ayatralian (like in the pictures) using their standard 240v outlets, I made an adapter plug and ran the charger off the dryer outlet. Now, get 67v out of the top exactly.  But when I plug this up to the euc, nothing.  After overnight it still didn't budge from 59.2v.  Also, the green light still never goes away.  So, on another hunch I open the batt compartment and place the charger on one battery pack.  Low and behold, the green light goes to red and the charger fan comes on.  It's now charging one of he three packs.  I've been riding on the original charge this whole time.   I think it's my connector port. The question is how to get to this. Do I need to actually open up the unicycle and split apart?  I think I really need to get a good look at that charging port. Suggestions? 

BTW, I will absolutely make sure that all three packs are pretty close in charge before I put take them back together. Don't want any equalizing voltage surprises. But since I'm assuming they're already wired in parallel, could my just charge them altogether?

H

[dmethvin]

If you unplug the charging connector from the battery you should be able to test continuity from the port on the outside all the way to the battery connector. There could be a break in the wires almost anywhere but the first place I would look if it's open is the back side of the charging port. Those are typically "solder pot" connections that have shrink wrap on them which could hide a cold solder joint or loose wire. You would need to strip off the shrink to inspect it.

I bought some spare connectors a while back and they came with wires and shrink on them. That is probably the way most vendors buy them too I suspect, so they don't even do the solder work. The work is really sloppy, I've attached a picture. There is barely enough solder on the wire to attach it and the shrink doesn't cover the solder joint! If yours are this bad they could easily be the problem.

 

[HJ]

 Greatly appreciated. My only question is how to actually get access to the backside of the charging port   I hate to have to split open the unicycle. Does the side panel  with the charging port on off switch come off easily, can I pry it off or is there more to it? 

[Chriull]

 

6 hours ago, HJ said:

... So, on another hunch I open the batt compartment and place the charger on one battery pack.  Low and behold, the green light goes to red and the charger fan comes on.  It's now charging one of he three packs.

You opened all the connections and are sure to just charge one? With the internal connections (daisy chain, see below) could be, that you are already chargin all of them?

 

6 hours ago, HJ said:

BTW, I will absolutely make sure that all three packs are pretty close in charge before I put take them back together. Don't want any equalizing voltage surprises.

Very Good Idea

6 hours ago, HJ said:

But since I'm assuming they're already wired in parallel, could my just charge them altogether?

H

Yes. But could be, that they (or some of them) are "daisy-chained" instead of "really" paralleled. Means the discharge output of one goes to the charge input of the next.

So you can charge the first pack of the serie and all should get charged.

But since you got/assume connection problems you should quite double check all the packs and connections - not that you get in the end again packs with different charge levels!

3 hours ago, HJ said:

 Greatly appreciated. My only question is how to actually get access to the backside of the charging port   I hate to have to split open the unicycle. Does the side panel  with the charging port on off switch come off easily, can I pry it off or is there more to it? 

No Idea - but as it seems, @chechohas his KS18 open and could know. 

[HJ]

6 hours ago, Chriull said:

 

You opened all the connections and are sure to just charge one? With the internal connections (daisy chain, see below) could be, that you are already chargin all of them?

 

Very Good Idea

Yes. But could be, that they (or some of them) are "daisy-chained" instead of "really" paralleled. Means the discharge output of one goes to the charge input of the next

It's possible, they could be changed, but I just connected three connectors and got three separate voltages. I charged him three separate voltages, and they  all charged independently, Each take me about 50 minutes to go from 60 V to 66v. But I need to figure out how to get to that charging port, so I can look at it. They did have to open the shells, because there's some waterproofing glue that I'd like to leave if I can holding them together. 

[HJ]

Ok, good news.  This morning I went into the euc and pulled the battery completely out.  There, underneath and too deep to view without actually taking the battery out, was a Deans type plug that had come apart.   I did continuity testing and sure enough the  proximal end goes right to the charge port.  Now, plugging in the charger....I get the light change to red indicating that the load is being seen and the euc is charging.   Work the problem, ya gotta love it.    Many thanks to all who helped me with this one.

Herb

[Yashaya Yasharahla]

On ‎2016‎년 ‎2‎월 ‎26‎일 at 10:18 PM, HJ said:

Ok, good news.  This morning I went into the euc and pulled the battery completely out.  There, underneath and too deep to view without actually taking the battery out, was a Deans type plug that had come apart.   I did continuity testing and sure enough the  proximal end goes right to the charge port.  Now, plugging in the charger....I get the light change to red indicating that the load is being seen and the euc is charging.   Work the problem, ya gotta love it.    Many thanks to all who helped me with this one.

Herb

Would have loved to see a picture of where the problem was since you opened it up. It could help us troubleshoot any similar problem  

[MetricUSA]

He did state he had no voltage at plug... A clue...

I'm surprised KS did not suggest solution when they knew of no voltage at plug...

[HJ]

On March 7, 2016 at 8:51 PM, Yashaya Yasharahla said:

Would have loved to see a picture of where the problem was since you opened it up. It could help us troubleshoot any similar problem  

Can't seem to upload    I'll keep trying     It was a simple deans type connector behind the top battery though  

h

[Michael de Gans]

I think he meant the connection from the charge port straight to the battery, which is weird because it's pretty tight and not easily taken appart.

 

 

(top right connection)

[HJ]

That is exactly it.  Never would have seen it if I hadn't pulled the to (680) battery out.   This might be more of a problem with the higher capacity models (1360) as the battery is really packed in there .

H