# WARNING !!!! Problems with TCCH charger!



## Siwastaja (Aug 1, 2012)

Well, the actual problem here is that the industry standard in using li-ion cells is to use a BMS. (Like it or not.)

While a no-BMS approach is a known kludge that has worked well for many people in many situations, it is still a "non-standard" way to do things, and you should expect problems in communication with experts and problems getting products that work just exactly as you want.

Of course their communication could have been more clear, but clearly, it's a technical misunderstanding between you and them. They assume you will be using the charger like it is supposed to be used, not for a "special" application.

It's possible that they simply cannot program the charger to your exact specification. It could be a large software development project that could cost at least several thousands of $.

Just my two cents. Of course the communication has been very poor, and if they cannot program a stopping current, the charger is quite limited. No charger should rely only on a BMS signal.


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## Coulomb (Apr 22, 2009)

Siwastaja said:


> Well, the actual problem here is ...


I think that a contributing factor is how the company refuses to release specifications on how to program it. Once it's programmed, there are few options for changing it.

There is the Elcon place in California, but no-one else apart from the factory seems to know how to program them. I don't think it's appropriate that every Tom and Harry programs their own, but the details should be made available so that those with appropriate programmers and expertise can change the program.

I mean, are they selling chargers or firmware?

Still, we don't have to buy from them; they can take this attitude if they choose. It's just a shame, since they seem to be pretty good chargers, if only they were a little more flexible.

Of course, I agree with the OP that not programming it as agreed to on the invoice is not good enough. Surely they could give instructions on how to post back the relevant PCB, to avoid Chinese customs problems. I've heard of the manufacturer having to send a complete new unit out, because they could not get the original through their customs for repair (even marked "for repair only"). I can understand their frustration with that situation.


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## Siwastaja (Aug 1, 2012)

I agree that it's ridiculous that you cannot program these chargers by yourself. What if you add cells in your pack or lose a few cells? Not only does the programming cost, it also causes a downtime.

This is one of the reasons I'm building my own charger.


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## kennybobby (Aug 10, 2012)

You may want to go thru Elcon for reprogramming, seems they understand how to meet customer specs, and shipping may be less hassle. http://www.diyelectriccar.com/forums/showpost.php?p=355402&postcount=51 

i would still like to see serial output from one of these chargers and try to reverse the programming--i'm surprised that it hasn't been done already.


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## pm_dawn (Sep 14, 2009)

Hi !

I have been in contact with Elcon in Sacramento and they will indeed reprogram the charger for me. But the problem is sending it there and shipping it back will be pretty much what I payed for the charger when buying it. Add to that the charge to reprogram the charger.

What I wanted to do by posting this thread is to inform those that have bought TCCH charger direct from factory that they might not have the charge profile that was agreed upon when ordering. And might actually be overcharging their cell without knowing.

I guess I'm on my own when it comes to whos fault it is. I could probably have been more clear on how I was going to use the charger and why the ending current was so important for this setup.

Still dont know how to solve the problem.

This is also the second charger that goes in to the car. I'm running out of charger funds.......

Regards
/Per


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## Ziggythewiz (May 16, 2010)

Well, they did get the end voltage correct, so if you were to specify a lower end voltage it wouldn't matter what current it shuts off at. I think people should be doing that anyway.

No need to taper the current at the end. Just turn it off at 90-95%


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## pm_dawn (Sep 14, 2009)

Well Ziggy, did you read the first post?

The charger is setup to 85,2v on 25 cells. that is 3,408v per cell in CV voltage.
How do you suggest I go any lower than that in ending voltage. If I go any lower the cells will not even charge anything. I think I'm been pretty cautious regarding to end voltage.........

The problem does not go away by lower the end voltage. It just gives me a slower charging and still overcharge of that one lower capacity cell.

I know that it has about 1,5ah lower capacity than the next lowest one.
That is why I have kept an eye on it in the later part of the charging.
That is how I found that if the charger would cut at 85,2 -85,5v and 5A that cell would still be safe and under 3,65v.

Regards
/Per


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## rwaudio (May 22, 2008)

It sucks and I hate to stereotype but that's the exactly response I've had from every chinese company that I've ever worked with. Once it's sold they consider the transaction finished regardless of if you got what you wanted/ordered/thought you were buying or even if they made a mistake. The only leverage I've had is a few have them started using paypal, so as long as the product arrives while you can still start a claim you have some level of protection. 

It's not an ideal solution but I used one of the simple programmable amp meters to create a charger using some modified Mean Well power supplies. First the power supplies were modified for CC-CV output, then alarms were set up in the meter so that I choose the termination current. Plug in the power supplies and it charges normally in CC mode, it hits the CV point and once the current drops below the pre-set value it triggers the alarm and turns off the charger. It's not ideal, however it has proven reliable and it's used every day in my friends lithium powered Solectria Force, I'm pretty sure he past 10,000km awhile ago using this charger.


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## Ziggythewiz (May 16, 2010)

pm_dawn said:


> Well Ziggy, did you read the first post?
> 
> The charger is setup to 85,2v on 25 cells. that is 3,408v per cell in CV voltage.
> How do you suggest I go any lower than that in ending voltage. If I go any lower the cells will not even charge anything. I think I'm been pretty cautious regarding to end voltage.........


Yes, I was mostly referring to anyone else who might order the same product. If your end voltage is at or below 3.4 VPC you won't overcharge the cells, even if the CV stage is longer than you'd like.

They will charge just fine at that voltage, unless you really need that last 1-5%.


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## Roy Von Rogers (Mar 21, 2009)

I'm a bit confused here. You say that charger reached the end point of 85v fine, but didn't stop at 5a, and one of the cells started to overcharge. What was the total voltage at that point when you manually ended the charge??

If it overcharged one of the cells, it should mean that the total voltage should have been higher then the 85.2v you specified.

Btw, I also have a TCCH charger from them ordered via a USA supplier, and I asked for 98v shut off at about 5a, and it doesn't shut of at 5a either, but it doesn't charge over the 98v, it just tapers down to that voltage, forgot what the ending amps are.

I was originally charging 28 HiPower cells, I bought 30 cells, just because they fit exactly in to the square I designated, this way I had two spares in case of a cell failure. 

I just recently tried an experiment, and added one more cell to see what would happen, I married the cell in via bottom balancing, so now I have 29 cells charging at 98v, at about 3.4 ending voltage per cell, and its working like a champ.

If you have an extra cell and room, try to see what happens, it may work for you, if you cant get satisfaction from TCCH.

Roy


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## rwaudio (May 22, 2008)

Roy Von Rogers said:


> I'm a bit confused here. You say that charger reached the end point of 85v fine, but didn't stop at 5a, and one of the cells started to overcharge. What was the total voltage at that point when you manually ended the charge??
> 
> If it overcharged one of the cells, it should mean that the total voltage should have been higher then the 85.2v you specified.
> 
> ...


For the exact reason that you bottom balance the voltages are all over the place at the top. When you hit the CV point and the current starts to drop off, depending on the cells, some voltages will continue to rise while others will fall. The actual CV point is likely maintained however the individual cell voltages can spread dramatically leading to what the OP talked about with a cell hitting 3.9v, I've also experienced this with my EMW 10kw charger, but I simply reduced the charge voltage from 3.45v to 3.40v per cell and all is well and I'm only down about 0.5Ah. This is also with a bottom balanced pack.


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## Roy Von Rogers (Mar 21, 2009)

Let me tell what I notice the other day charging and rechecking the cells. I noticed some of them coming up quicker then others, and at first I thought that maybe I hadn't bottom balanced them correctly, even though I let them sit for 24 hours or more when I got the final 2.7v per cells.

Some cells came up faster, but as the pack was getting fuller, those cells slowed down and the others were catching up. I actually stopped the charger before it finished, I had to leave. But the cells were all between 3.35 and 3.39v at .8 amps when I took the charger of.

I feel much better now that I put the extra cell in, for I know at least there is no way for them to ever overcharge, unless there is a charger failure, and my JLD404 will take care of that.

Not to mention there is little energy at the top, and its better for the cells to stay at the lower end of the charging cycle.

I'm also amazed that no one has figured out how to change the charging profile on these TCCH chargers. I really don't like the idea of using another electronic device to set the profile via can bus, since I have no use for active balancing schemes.

Roy


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## pm_dawn (Sep 14, 2009)

@ziggy

The problem is that I have charger that does a too long CV phase.
If I could get it to do CC only I would be better off.

The problem when going down in charge current is that cell that are higher capacity tend to fall a little bit in voltage when the current decreases, that makes room for the lower capacity cells to go even higher in voltage without the whole pack going to high.
So @5A most of the cells would be 3,39, leaving one cell to go up to 3,81 and over without the charger knowing.........


@Roy 
I dont know if you have ever checked your cell voltages during the last part of the charge. Then you would have observed exactly what rwaudio and I has described here. It is a series string..... all of the cell will not have the same voltage during the last part of the CV phase. I only have 1,5ah difference in my pack, that is about 1,5% on these 100ah cells, and still that makes one cell go really high if the charger keeps charging at those low currents.


@rwaudio
It is a sad experience. For sure. Guess I need to start building my own charges from here on. Damn ! How hard can it be to sell a charger that can be reprogrammed within certain limits and not cost an arm and three of your legs...... 
I like your solution with the current meter, I guess you mean the lightobject meters. I have been thinking about using the voltage version of them to safeguard the cell that is lower capacity and use that meter to shut off the charger. But using the current version on the dc charge lead might just be a notch smarter. That way I would not risk introducing any parasitic load on any cell. Might be the best solution here. Then I could actually change the ending current by just reprogramming the meter.

Thanks for the idea !

regards
/Per


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## frodus (Apr 12, 2008)

The only problem I see, is if your charger is not plugged in, the alarm will be "active" because the charge current would be under 5A..... so when you plug the charger in, it will already be disabled. You may need to start it manually, then once it's charging, enable the alarm.

So I see it running once the meter sees current flowing, but how does the charger start?


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## pm_dawn (Sep 14, 2009)

@Roy

I'm sorry if I offended you. You must have the most consistant pack I have ever heard of. But on the other hand you really undercharge those cells really nice.

Maybe I should try to go even lower in CV voltage.

I still have the other charger from BMSbattery. That charger was adjustable both for max current and CV voltage. But I could not chage the ending current on that one either.

I have to ask you Roy, when does your charger shut off, at what current ?

Best Regards
/Per


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## pm_dawn (Sep 14, 2009)

frodus said:


> The only problem I see, is if your charger is not plugged in, the alarm will be "active" because the charge current would be under 5A..... so when you plug the charger in, it will already be disabled. You may need to start it manually, then once it's charging, enable the alarm.
> 
> So I see it running once the meter sees current flowing, but how does the charger start?


Hi !

yes I know that this could be a problem. But I guess some kind of latching relay that is powered by the ac input could solve this. I would of course use the enable cables on the charger to disable it when current falls under the preset.

regards
/Per


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## rwaudio (May 22, 2008)

pm_dawn said:


> @rwaudio
> It is a sad experience. For sure. Guess I need to start building my own charges from here on. Damn ! How hard can it be to sell a charger that can be reprogrammed within certain limits and not cost an arm and three of your legs......
> I like your solution with the current meter, I guess you mean the lightobject meters. I have been thinking about using the voltage version of them to safeguard the cell that is lower capacity and use that meter to shut off the charger. But using the current version on the dc charge lead might just be a notch smarter. That way I would not risk introducing any parasitic load on any cell. Might be the best solution here. Then I could actually change the ending current by just reprogramming the meter.
> 
> ...


Yep, basically just like one of the lightobject meters, however the one I found works on AC input voltage (85-265) instead of the usual DC 9-30v so it just comes on with the charger. I got it on ebay a couple years ago but a quick search didn't bring it up, might be still available somewhere. It's handy, easily programmable and has been reliable.

I had contemplated setting up a short range / full range switch that would switch between the two alarm outputs, one configured with the usual 5A termination (for a 100Ah), and the other configured for just below the CC current, that way there would be no CV phase. You might be a few Ah short on the charge but might help the lifespan of the pack, if you knew you needed all the range you can get, you toggle to the 5A setting. Something similar could be done with a programmable volt meter to terminate at a lower voltage in the CC stage if you wanted to try charging to 80% or something like that. Just make sure the charger will still terminate on it's own and doesn't rely completely on the meter to terminate.


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## Roy Von Rogers (Mar 21, 2009)

pm_dawn said:


> @Roy
> 
> I'm sorry if I offended you. You must have the most consistant pack I have ever heard of. But on the other hand you really undercharge those cells really nice.
> 
> ...


You know I don't know anymore..lol. Next time I do a full charge I will have to look at it again. I have a Kill-A-Watt meter on my cord and I just look what the ac amps input to the charger is.

I don't drive a long ways most of the time, if I put 20 to 40 miles on the odometer I just plug it in and go in to my office, and when its time to go home to eat, I just unplug. I may come back later to my office and plug it in again to finish the charge. At times I just look at the KillaWatt meter before I unplug to see the amps. Sometimes its at 8 or 5 amps ac, sometimes its below 1 amp. I don't really care since I don't drive a lot of miles.

But as mentioned earlier, I lifted the truck bed up and charged, just to do a cursory check on the cells, and found what I wrote about.

Now here is my take on your problem. If you have a charger that suppose to shut off at xx voltage, and one of your cells goes too high, there are only two possibilities, either they were not properly bottom balanced, that's getting them to 2.7v per cell, and waiting at least 24 to check voltage and correct, or you have a cell that's lower in capacity then the rest.

Now if you bottom balance as I have stated, and let the charger go, and measure the amp hours going in, the first cell that hits 3.5 v or over, is the lowest capacity cell, and if its under the rated factory amp hours, you need to replace it, or run your vehicle by that ah restriction.

Don't worry about the series thing, if you have 100ah cells and you put in 100ah, the cells are full, and they should be at the voltage the charger is set to. The only reason that one cell is too high, is because of what I stated earlier.

The main thing is the bottom balance, for if that's not done right nothing we talk about has any meaning. And I have to tell, doing it correctly is a PITA.

I know you wanted that thing to turn off at 5 amps, but it is what it is unless they correct it for you. But never the less it should turn of at the voltage you asked for.


Roy


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## Siwastaja (Aug 1, 2012)

Roy Von Rogers said:


> Let me tell what I notice the other day charging and rechecking the cells. I noticed some of them coming up quicker then others, and at first I thought that maybe I hadn't bottom balanced them correctly, even though I let them sit for 24 hours or more when I got the final 2.7v per cells.


You probably bottom balanced them just fine and that's exactly the reason why you see what you see; balancing on bottom means unbalancing on top.

You need to top balance if you want them to have even voltages at the end of the charging.

If you want to bottom balance, then you need to adjust the charging voltage low enough that none of the cells exceed 3.65V (or preferably less than that). You can only do that manually by monitoring every cell and lowering the charger voltage as long as any cell gets too high.

For this reason, an unadjustable charger is a nightmare for a bottom balancer. If you top balance, you just get the charger with number of cells times 3.65V or whatever you want to use. When bottom balancing, it's an iterative process that requires at least one measurement run.


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## Roy Von Rogers (Mar 21, 2009)

Siwastaja said:


> You probably bottom balanced them just fine and that's exactly the reason why you see what you see; balancing on bottom means unbalancing on top.
> 
> You need to top balance if you want them to have even voltages at the end of the charging.
> 
> ...


Why are you posting this, did you read anything I wrote ??

Btw a bottom balance is not a nightmare, its just something you have to do, unless you want to eat a cell if you ever go too low.

If you would have quoted the rest of my post, it would have show that the cells were within .3v to each other. Your not telling me anything I'm not aware of, why are you attempting to give me advice.

Btw are you by any chance related to the guy that Jack Rickhard had to boot off his blog.

Roy


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## TTmartin (Feb 7, 2012)

Siwastaja said:


> You probably bottom balanced them just fine and that's exactly the reason why you see what you see; balancing on bottom means unbalancing on top.
> 
> You need to top balance if you want them to have even voltages at the end of the charging.
> 
> ...


Hi,
I have a bottom balanced pack, 73, 100AH cells.
I am in the process of arriving at an end voltage for my Zivan ng3 charger, so it can be reprogrammed by my supplier. 
I have one cell that hits 3.5v when the pack reaches 249 volts, so that is the end voltage the charger needs to be set to. If the c/c phase is only around 10 or 11 amps from this charger what am I gaining by the c/v phase if the pack is bottom balanced?
By design a bottom balanced pack is out of balance at the top so as amps drop in c/v phase it causes some cells to drop in voltage well others keep rising.
I'm thinking it would be better to just use c/c for a bottom balanced pack when charging at 10 or 11 amps?

Please go easy on me I'm new to all this I've charged my pack 6 or 7 times and this is the conclusion I've come to so far?
I also have 2 JLD meters which will over ride the charger monitoring AH and voltage.


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## Hollie Maea (Dec 9, 2009)

Roy Von Rogers said:


> Btw are you by any chance related to the guy that Jack Rickhard had to boot off his blog.
> 
> Roy


You could found a city with all the people Jack Rickard has booted off his blog for disagreeing with his Church Of The Bottom Balance.


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## TEV (Nov 25, 2011)

pm_dawn said:


> Hi !
> 
> I have been in contact with Elcon in Sacramento and they will indeed reprogram the charger for me. But the problem is sending it there and shipping it back will be pretty much what I payed for the charger when buying it. Add to that the charge to reprogram the charger.
> 
> ...


This may help you : http://priuschat.com/threads/elcon-charger-end-voltage-and-other-mods.104914/


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## Siwastaja (Aug 1, 2012)

Roy Von Rogers said:


> Why are you posting this, did you read anything I wrote ??


Maybe I did misread you, but I thought you were kind of "expecting" balance at top with a bottom-balanced pack, being surprised that it wasn't so in reality, so I offered an explanation.



> Btw a bottom balance is not a nightmare,


Didn't say so, I said this particular _charger_ is a nightmare for people who want to bottom balance, because if you want to bottom balance properly, you need to adjust the charging voltage quite exactly on the first time you charge. And if the only way to change the voltage is to send it to the manufacturer, it's quite a slow and expensive process! So get a charger that allows _you_ to change the voltage if you want to bottom balance properly. But most probably, you already know all of this.

No-bms bottom balancing is not only about the balance itself, it's a complete procedure that needs to be followed and the charging side is a bit "tricky". You probably know this already, but just making sure.

TTMartin explained the full process the best way I've ever seen written anywhere: http://www.diyelectriccar.com/forums/showthread.php/upgrade-lithium-88625.html . No news for you, I guess.



> Your not telling me anything I'm not aware of, why are you attempting to give me advice.


OK, I think I misread you then, sorry. But no harm done, someone else may still need this information. Good luck anyways.

PS. I will not read your reply. Thanks.


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## kennybobby (Aug 10, 2012)

TTmartin said:


> Hi,
> I have a bottom balanced pack, 73, 100AH cells.
> ... By design a bottom balanced pack is out of balance at the top so as amps drop in c/v phase it causes some cells to drop in voltage well others keep rising.
> I'm thinking it would be better to just use c/c for a bottom balanced pack when charging at 10 or 11 amps?


I would agree with you that yes it is better to just use the CC charging and end it at 3.6 vpc times the number of cells. It will not be 100% charged without doing the CV procedure, but there is little more energy to be gained versus the risk of overcharging if it doesn't shut off at C/20 amps during CV. 

@ Per 

Can you find out from them what the other 9 mode settings in your charger might be. One of them might be a cutoff after CC when the voltage reaches your desired set point. There is a tiny pushbutton located under one of the labels that changes the mode to one of the ten modes that come programmed. It might only get your pack to 95% SOC, but at least it would be a solid cutoff point that you wouldn't have to worry about overcharging, such as during the CV mode that it is doing to you now.


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## EVfun (Mar 14, 2010)

Roy Von Rogers said:


> Some cells came up faster, but as the pack was getting fuller, those cells slowed down and the others were catching up. I actually stopped the charger before it finished, I had to leave. But the cells were all between 3.35 and 3.39v at .8 amps when I took the charger of.
> 
> I feel much better now that I put the extra cell in, for I know at least there is no way for them to ever overcharge, unless there is a charger failure, and my JLD404 will take care of that.


You need to follow that to the end of charge before you declare that! With bottom balanced cells once the voltage limit is reached some cells will continue to increase in voltage, others will decrease in voltage and the declining current will allow those cells to decrease in voltage. I've had the opportunity to do this test with several 8 cell packs of Headway cells. I find little cell to cell variation until the first cell gets to 3.45 volts. That is about the point where small changes in SOC start making much larger changes in the cell voltage at a given charging current for those, and for my EV Thunder Sky pack too. Even top balanced cells start showing this spread over around 3.55 volts.


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## PStechPaul (May 1, 2012)

If there is just one lower capacity cell that rises in voltage first, it might be possible to use just a single mini-BMS on that cell and have it start shunting or turn off the charger.


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## Siwastaja (Aug 1, 2012)

PStechPaul said:


> If there is just one lower capacity cell that rises in voltage first, it might be possible to use just a single mini-BMS on that cell and have it start shunting or turn off the charger.


No it isn't, because miniBMS uses a significant amount of current and will unbalance the pack quickly if there is a module only in part of the cells. Any shunting happening would also ruin the bottom balance.

A BMS with very negligible current consumption could be used like that, and the shunting should be disabled, only monitoring used to turn off the charger.

But it might give false sense of security; at least you'd need to check the situation every now and then.


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## pm_dawn (Sep 14, 2009)

kennybobby said:


> I would agree with you that yes it is better to just use the CC charging and end it at 3.6 vpc times the number of cells. It will not be 100% charged without doing the CV procedure, but there is little more energy to be gained versus the risk of overcharging if it doesn't shut off at C/20 amps during CV.
> 
> @ Per
> 
> Can you find out from them what the other 9 mode settings in your charger might be. One of them might be a cutoff after CC when the voltage reaches your desired set point. There is a tiny pushbutton located under one of the labels that changes the mode to one of the ten modes that come programmed. It might only get your pack to 95% SOC, but at least it would be a solid cutoff point that you wouldn't have to worry about overcharging, such as during the CV mode that it is doing to you now.


I have no idea if the charger actually has more than one charge curve. I have not tried to change it yet. but it seems I might have to start reverse enginer this motha sakka, unless they will refund me for the charger. Which I highly doubt at the moment.
I would settle for CC only as a solution. That would not leave that much capacity out at a full charge perhaps about 2-3%. 

We will see what happens.
I tried to reach them again today.
no reply yet......

I'll keep you posted.


Regards
/Per


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## Roy Von Rogers (Mar 21, 2009)

Hollie Maea said:


> You could found a city with all the people Jack Rickard has booted off his blog for disagreeing with his Church Of The Bottom Balance.


 
If you had spend anytime there you would know who I was talking about.

As far as I know he was the only one. If there were others, pray tell.

Roy


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## Red Neck (Feb 1, 2013)

If you do end up stuck with the charger as is, and if you have any way of programming your drive train's controller, top balance your pack and set
a cutoff voltage for your car in your car's controller for when your battery
pack reaches the voltage where your lowest empty cell reaches 2.5v under
load. That way your charger will charge them ideally, whereas your controller will take care of preventing over discharge of the battery pack, most importantly, its weakest cell.

Not that inspiring to see though that some posters lack some basic courtesy and in general, that top or bottom balancing has somewhat of a religious nut following on either side. 

If you have access to your controller's settings, top balancing is easiest and you set the pack so the charger stops charging when reaching 3.5 or 3.45v.

If you don't and can reprogram the charger, you can bottom balance, or throw in an additional cell and you prolong the life of the entire pack by undercharging it constantly..

No need for overly zealous defense of either of the approach. I am quite displeased that Jack like psychological instability so easily engulfs other EV patrons that easily. Regardless of whether they use top or bottom balancing.
I use both, depending on chargers I have and whether I can set the controller of the car.


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## mk4gti (May 6, 2011)

Red Neck said:


> a cutoff voltage for your car in your car's controller for when your battery
> pack reaches the voltage where your lowest empty cell reaches 2.5v under
> load. That way your charger will charge them ideally, whereas your controller will take care of preventing over discharge of the battery pack, most importantly, its weakest cell.


Most (if not all?) controllers do not go down to the cell level. Yes you can program certain controllers to back off at a certain pack voltage but it would not protect a bad cell/unbalanced cell from damage.


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## pm_dawn (Sep 14, 2009)

@Red Neck

It an interesting suggestion, but I fear that it will limit the usage of the vehicle a bit more if I use the controller configure/top balance solution.
The voltages are really very moving targets when driving the car, because of the varying current. 
But for charging I pretty much know what current is going to be max.
It is just so much easier to measure how all the cells behave when you have a pretty constant current. So to find the correct voltage+current combination on the charging end is just so much simpler.

But I'm open to all suggestions. I'm not religious in the bottom balancing corner, but the more I look at it the more I like it.....

REgards
/Per


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## kennybobby (Aug 10, 2012)

@ Per

Here is a document of the charging profile with the labels they use for the setpoints--may help you be able to tell them what you want it to do.


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## pm_dawn (Sep 14, 2009)

Hi !

I don't think that the Litium version of the charger has more then one chargeprofile if it is deliverd from factory.

But I will check.

Thanks.

Regards
/Per


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## Red Neck (Feb 1, 2013)

I use the controller's cutoff function to protect the cells on one of my smaller city cars, so it first lowers current when it gets near cutoff (which also eliminates overly sensitively treating the sag, since sag is lowered by lowering the current), and then it cuts off when the lowest cell hits 1.7v, because 
I emptied the pack slowly and measured the lowest cell when doing it
and set the bottom pack voltage then. This was in winter. In cold, the cells sag more quickly so 1.7v is actually high, and would be over 2.5v summer at same SOC and current. This works VERY WELL. And I use a TCCharger (for lead acid)..

Lithium TCCHARGERS come with no profiles since the BMS is supposed to steer them. He has a lead acid one. 

You all way underestimate how much you can achieve by your controller's settings. You set it so that as you reach some 30%SOC, to limit torque to some 80% and when you reach 20% to 60% and then to limp at 10%... for instance.

Trust me, with a dumb charger, with set voltage, top balance and use your controller to prevent the weakest cell from overdischarging. Just empty the battery pack with driving to a reasonable level with driving and then slowly with lights, heater, etc and measure the weak cell and then total pack voltage to know where you are at.


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## dtbaker (Jan 5, 2008)

kennybobby said:


> @ Per
> 
> Here is a document of the charging profile with the labels they use for the setpoints--may help you be able to tell them what you want it to do.



the Elcon guys in sacramento do a great job re-programming the Elcons to specs you ask for. If you ask for curve 620v the user-clickable setter can change the voltage +/- 5v in 1v increments. curve 613 gives you +/- 5 clicks with 3.2v increments in case you change number of cells.

I have been very happy with good initial top balance, letting the chargers do their job at the end-of charge, and setting low voltage limp voltage if using zilla/soliton controller to catch low voltage conditions. The LiFePO4 cells just don't seem to drift much at all if the initial balance is good, so I am just check/rebalancing once a year now.


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## pm_dawn (Sep 14, 2009)

Hi !

Time for an update.

I have been banned from TCCHs mail server after I started to request progress report every day. That was about a month ago.
I got really tired.

Here is a copy of the auto reply I get from their server.

----------------------------------------------------------------

抱歉，您的邮件被退回来了……
原邮件信息： 　
时　间：	2013-10-18 14:20:15
主　题：	Progress report !
收件人：	[email protected]
退信原因：	
发件人被对方拒绝，可能是对方设置了黑名单或者过滤器等相关限制。
英文说明:User rejected.(User reject).(User reject)
建议解决方案：	
请联系收件方，将发件方邮箱地址从收件方的黑名单中移除。

----------------
This message is generated by Coremail.
您收到的是来自 Coremail 专业邮件系统的信件.

------------------------------------------------------------------


But I suspect that i'm out in the cold now.

I heard from another user here at DIY that had the exact same problem.
I hope you add your story to this thread.

I'm going to try to call to TCCH and see if I get some action.

Btw the vehicle is not in use right now.


Regards
/Per


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## pm_dawn (Sep 14, 2009)

Hi Again !

I called TCCH and got to talk to Nancy.
She sent me an email again.
I answered that Email and it seems my emails doesn't bounce anymore.

We will se what will happen.....

Regards
/Per


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## Weisheimer (May 11, 2009)

Per,

Ask her if they have available a "re-programming plug in device" that is pre-loaded with your new charge curve.
John Hardy in England mentioned that TCCH was going to send him one, but I have never heard if they actually did send it.
It would be cheaper than sending the charger back and forth!

Cheers

Mark Weisheimer


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## pm_dawn (Sep 14, 2009)

Hi Mark !

That is exactly what I have asked for.

I know from John that he has received the device but not yet used it on his charger, as of the last time we corresponded.

So Yes that is what i'm hoping for.

Better Yet just a file and a good description on how to flash it into the charger.

Zero cost of hardware and shipping for them.
Just the time to do the flash file......


We will see what happens.

Regards
/Per


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## Weisheimer (May 11, 2009)

Per,

It will be interesting to see what comes of this.
The Future Devices Inc LPC9XX USB-ICP programmer would allow you to load a hex file via the 5 pin ICP connector that is on the logic board.
It also has supporting software to allow loading 1K blocks as well.
I am curious to know which port their programmer will use.
It might plug into the round 7 pin connector on the side and thus program via the serial port.

Please keep us updated as you find out more.
I wrote John at his tovey site this week, but I haven't yet received a response.

Best

Mark


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## PIFOUBMW (Dec 19, 2013)

Hello from FRance,

I have exactly the same problem but I ordered for 70celles 255,5V maximum voltage and my seller sent a 292V 21,6A not configured TCCCharger 6KW, My batteries charged up to 290V !!!!!!!! In Emergency I cut the power supply manually and connected the batteries to the OEM PACK of my PRIUS PHEV to reduce voltage under normal limit and I saved my batteries A123.

But now I don't know how to modify myself the voltage limit because I have no BMS to stop the charge.

Anyone know how to reprogramm it ?

PIFOUBMW


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## dtbaker (Jan 5, 2008)

PIFOUBMW said:


> Hello from FRance,
> 
> I have exactly the same problem but I ordered for 70celles 255,5V maximum voltage and my seller sent a 292V 21,6A not configured TCCCharger 6KW, My batteries charged up to 290V !!!!!!!! In Emergency I cut the power supply manually and connected the batteries to the OEM PACK of my PRIUS PHEV to reduce voltage under normal limit and I saved my batteries A123.
> 
> ...


as far as I know the TCCH chargers have proprietary software internally, and need to be re-programmed by official resellers...... not recommended for end users.


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## Roy Von Rogers (Mar 21, 2009)

Who was the seller, you need to contact them to correct.

Also A123, or any other prismatic cells for that matter, should never be charged to more than 3.6v per cell, your charger should be set to max of 252v.

I'm charging my 100ah, at 3.4v per cell, and the little extra on top loss, is not enough to even worry about.

Much better and safer to stay at the lower end.

Roy


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## PIFOUBMW (Dec 19, 2013)

My french dealer ordered it on a low price site : www ec-power eu the product is working but I have to reduce myself with potentiometer the current at the end of charge and cut manually then I stay near my charger with voltmeter during 2 hours ...

My dealer asked to have 255,5V (2,65V/cell) but the seller sent it without configuration ...


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## Roy Von Rogers (Mar 21, 2009)

I need to add that when I'm talking about prismatic cells, I'm talking about the ones most of us use, Lithium ion types.

I know there are some cells coming out that have a different chemistry and are charged at other rates.

Roy


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## simthhope05 (10 mo ago)

Oh really 


Sent from my iPhone using Tapatalk


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