Fazua Battery Mystery how do you get 36V from 17 Batteries

[eMark]

Deleted

Maybe he was going to post a CAD of his 7+7+6 end-to-end cell alignment of Wayne's Fauza 10s2p pack. Possibly decided to make some additional corrections before posting it :thumb:

It is nice to know that Hh is also interested in end-to-end cell alignment as are the Electrical Engineers that designed this Fauza 10s2p battery (without potting) and other engeneering end-to-end 18650 cell configurations.

Perhaps Wayne will decide to disassemble and reassemble trying some used/salvaged cells to see if the BMS is still good. If he does some closeup photos of the end caps and connections would be of interest to those planing a DIY end-to-end cell configuration.

.. occasionally my pack is going into an error state after charging, if I leave it for a few days it’s good again. I’m guessing a few bad cells are triggering high voltage cutoff and it takes a while for the bms to pull them down again. ... So I may need to replace some of the cells.

If your pack also has end-to-end cell alignment and you decide to replace some or all of the cells could you post some closeup photos of the end caps and connections as more and more ES members are interested in designing and building non-weld/solder packs.

Hoping Hh will provide a CAD, digi-image, or drawing so as to validate his 7+7+6 end-to-end Fauza cell configuration. Inside of the Fauza battery enclosure is barely 11" in length.

Hopefully with Hh's knowledge he will post a "7+7+6" CAD or freehand drawing of the end-to-end cell configuration in Wayne's FAUZA 10s2p battery. Otherwise how are we to believe his 7+7+6 cell configuration is even feasible within the dimensions of that Fauza pack (11.61"x3.15"x2.95").

Here's my digi-image as a compromise to Hh's 7+7+6 inline cell configuration of Wayne's FAUZA 10S2P battery. Purposely made it as simple as possible so that Hh's forthcoming professional CAD or hand drawing will prove his 7+7+6 cell configuration :thumb:

 

[Hillhater]

Deleted

Maybe he was going to post a CAD of his 7+7+6 end-to-end cell alignment of Wayne's Fauza 10s2p pack. Possibly decided to make some additional corrections before posting it :
Hoping Hh will provide a CAD, digi-image, or drawing so as to validate his 7+7+6 end-to-end Fauza cell configuration. Inside of the Fauza battery enclosure is barely 11" in length.

Actually, i started to post a picture of a 7 cell group......
..but then i realised that ..
1) there was no need as the OP had already posted them in the first post,.and...
2) ..pointless as you obviously have a mental and visual problem with recognising what is in front of you.!
All the answers are right there in the first post.
Why do you refuse to comprehend a group of cells, one in the center and 6 surrounding it ?..IE , 7 in total ?
Just look again at that original photo, you can actually SEE the center cell in the final group of 6, (at the right) as one cell is missing on the outside ,...or go get a handfull of 18650s , a rubber band , and play for a while !.
PS... do not assume those cells are CONNECTED end to end !...
.....there is a distinct difference between cell layout (7+7+6), and pack connection, (10s, 2p)
Oh !, and by the way, a 7+7+6 configuration could fit in an enclosure 2.5 ins x 8 ins

 

[eMark]

Your such a good sport ... carry-on

 

[Ianhill]

I had a a2b metro few years back faulty bms, all cells showing under 1v so first isolated the bms from the pack then used an rc charger on a nimh setting and slowlly tickled the cell groups 1 by 1 upto 3.0v so the charger would start in lithuim charge balance mode and give the pack about 20% charge state and left them over night to check how they settle any faulty cells will show in a day or 2 with drifting voltages.

I was lucky the Sanyo cells charged up and worked well the controller i used allowed me to setup battery current and i used a wh meter so i could see under full load they were still holding voltage up strong but ive also had packs that have taken a charge but they max out to 4.2v under charge with low currents same for discharge they fall flat on their face game over, your pack is fairly new and decent quality so id say the bms is responsible if repaired or swapped no reason you wont get a year or few from the pack like i managed.

 

[Waynemarlow]

Sorry guys I've not had time to pull the pack apart. There is some chatter on other forums that Fazua have indeed put the firmware in Ram and not Eprom. Not sure where thats going to leave this pack as surely the ram has now fallen over.

EMark, as much as you want to put your theories across, you are way wide of the mark. Just accept that Hillhater is on cue and the setup is a 7-7-6 arrangement. As yet I suspect that the cells are hard welded in, but I won't know that until I start to disassemble it.

Thanks all.

 

[jbalat]

There is some chatter on other forums that Fazua have indeed put the firmware in Ram and not Eprom. Not sure where thats going to leave this pack as surely the ram has now fallen over.

No!!!!!!!!

 

[Hillhater]

Sorry guys I've not had time to pull the pack apart. There is some chatter on other forums that Fazua have indeed put the firmware in Ram and not Eprom. Not sure where thats going to leave this pack as surely the ram has now fallen over....

..Junk the BMS !...you have little to lose, and it was probably the cause of this situation in the first place.
Either way you will need to manually “nurse” this pack checking , charging , etc,..if it has any future at all.!

 

[Waynemarlow]

Sadly some of the manufacturers do a battery check on start up and unless the battery responds ( I'm guessing the 4 wires going to the BMS from the motor are data signal wires ) with their own data response, then the motor will not start. Certainly I'm aware that Bosch and Yamaha do it this way. Does Fazua, we will have to see.

 

[Hillhater]

Your call.
Keep us updated on how it works out. :wink: :wink:

 

[benwilliam]

very interesting
I also try to wrap my head around this battery.

without opening it what I can see so far:

Output side:
Rosenberger2 plug with 2+4 pins
The main pins are off (no 36V)
one of the small pins provides 12V, I assume those 12V are used for Motor and Sensor electronic and if available also for light (optional connector box).
The Battery gets (on one of the other pins) from the motor controller a "GO" and it enables the main output with 36V

Input/Charging Side
Here it seems also weird for me. There is also a Rosenberger 2 plug with 3 pins.
I thought this 3rd pin is just a temperature sensor, but it seems to be more.
When I apply 42V@2A the battery does not charge.
My assumption is, that it needs also some kind of signal on the 3rd pin.
Does anyone has an idea what those signal could be?

 

[jbalat]

Ben,
when charging a bosch battery the 3rd pin is a 5v signal which opens to battery up to accept charge.

Is it possible to create a bridge between the charger and the battery so that it is easier to measure the voltages on the other pins back to ground ?

Otherwise open the charger up and measure from the inside as it is charging

 

[benwilliam]

On the Charger side the 3rd pin does not have 5V, so I dontt think it is the same as with bosch.
Yeah trying to sniff the 3rd pin will be my next step

 

[jbalat]

Some disturbing news, one of the users in the fazua FB group has removed his bms in order to balance his cells which were pretty bad however after putting it back together he now feels that he has lost connection with the bike. Sounds like the rumour may be True.

What do you think the odds are of reprogramming the BMS ?

BTW mine has bad cells too and I have pulled it out of its case but hard to make heads or tails of where the cell pairs are or even how the cells are connected with each other. Will dig into it more but in order to keep the bms alive do you think it’s sufficient to power it with another 10s battery via the balance leads only ?

 

[Waynemarlow]

Sorry I've been a tad busy and not been following the thread, apologies.

OK so others are having problems with the Fazua batteries and it would seem more than a few.

Mine is simply a manufacturing fault, possibly a dangerous one. I'm theorising a bit, but to my very untrained eye, when the packs were built the spot welding tips didn't have enough tension and by consequence have burnt through the connecting plate, leaving a very poor weld. These thin welds look like they have then over heated under load and heated the cells themselves. One of my cells has actually leaked throughthe spot weld. I've attached a picture to have a look at.

All the other packs look OK and all the cells have charged up to 3.0 volts and held for a couple of weeks so pretty happy with them. Its just two cells that have gone almost to 0 volts and need replacing.

When you actually take the packs apart, the layout is actually pretty self explanatory with the 1 st pack simply laying across the top of the two groups of cells.

Charging is more complex than I thought. There are only 2 wires to the main charging port + - and yet on another good pack I have, a standard charger will apply 42 volts, but no charge takes place. This is a right pain as the connector is available relatively cheaply and a 4 amp charger for a scooter or such like is also very cheap. The combined lead and charger is less than 1/2 the price of a Fazua charger.

So how the heck does the pack signal to the charger to start charging or how does the pack know its not a Fazua charger through just two wires ?

If you guys need any photos or directions how to dismantle the packs let me know. My plan is to simply replace the two cells with a couple of cells I have already on hand and see what happens. I'm wondering if the internet chatter on the board not holding up memory when the voltage is taken off is being confused with the non charging if you're not using a Fazua charger ?

 

[jbalat]

Wow thats great you identified the root cause. It may be worth contacting Fazua about this with a few pictures and see if they will replace it. Regarding the BMS firmware I did manage to get a copy of it but it would need a full version of the toolbox software to flash it so you would need to take it to a bike shop that services fazua bikes, whether the bootloader is still present is another matter so maybe it wont flash ???
Anyway one of the users says his battery was not recognised after disconnecting the BMS and then he said after a few days it worked again. He has been very vague and not really replying to my emails so am still not confident in my mind whether we can disconnect the bms or not.. I accidentally bumped the ground lead on my battery and it came off, I quickly reconnected it and put the battery back together and luckily it still works. Needless to say it still throws random errors now and again under load but fixed by holding down the reset switch. Under no load the cells were perfectly balanced. I even measured them while charging under 2 amps and still balance was good.

 

[Waynemarlow]

Jbalat, by any chance are you getting your battery problem when about 2/3 discharged and under full power mode ?

I ask this question as the cells are Samsung 35E cells which have a max rating of 8A's. Now they are a 10S2P pack, so the pack has an upper rating of only 16A's @ say 34 volts = 500W's approx. We built a few 48 volt packs using these 35E cells thinking they would give a greater capacity over the Samsung 30Q's we had been using, only to discover that in the bottom 1/3 of capacity, the voltage sag at around 400W's would trigger the BMS low voltage shut down, forcing a disconnection and reset using a charger. From our field testing we reckon they only have a 5A rating at 1C in the lower voltages. We were pretty disappointed with the cell as in effect they gave less W/hs than the 30Q's in riding conditions.

Now that was a 13S2P pack so I would expect the 10S packs to have a tad lower than 400W's which then puts it directly in the firing line of the Fazua's 300W max rating. But looking at the settings file of one of my drive packs its set to 400Ws and 32kph which I would suspect an American setup, which is the same as Australia ? Now that drive pack would definately trigger the BMS shut down if the 35E's voltage did sag, requiring a reset.

I contacted Fazua re the battery but have had no reply as yet. All in all the Fazua experience has been relatively dissappointing. If you at all intend to tinker with any part of the system, whether it is the battery, drive, bottom bracket, then walk away and buy a Bafang system. Fazua have made every part only accessible by Fazua and every part of the system is constantly logged in use. All settings and user max's are held in EPRom, only accessible by Fazua. It would seem also the 3 units all have to talk to each other, agree that its a working system, before it will begin to operate. That means we are obligated to only use factory units that can only be repaired at the factory and can only be serviced by Fazua dealers. That incidentally is against EU consumer law but as we are no longer in the EU, I guess I can't complain.

Would I recommend Fazua to any reader here, got to say its a pay and play system, most readers here are tinkerers and like investigating how things work, pay and play is not really us.

 

[jbalat]

Wayne my experience with my bms fault is very confusing.. it will only trigger while it is less that a 1/3rd discharged so plenty of capacity and I’m only using eco 120w max.. I actually tried to get it to trip when it was 2/3rds discharged going up a hill in the rocket 300w setting but it did not falter. I’m stumped. I bought a second battery and that one has not had any issues at all.

I am getting power drop offs randomly on my way home dropping from 120w to 40w every now and again on both batteries. It is during constant peddling and I monitor the user power which is staying consistent. I put this down to maybe motor overheating or momentary disconnection of the battery going over bumps. It is disturbing. There is lack in the fazua app that can’t detect or show these issues so it is hard to diagnose. Yes it is rideable so I guess I can still sell it off.

Overall I was impressed with the design side but it hasn’t been a reliable system in my books.

Let us know if replacing the 2 cells fixes yours and whether the bms comes back to life again. Good luck !!

Btw I wish we had the 32km law like US and New Zealand but we are stuck with the 25 law.. it sucks that fazua will not honour warranty if your bike isn’t flashed with the correct settings for your location

 

[Waynemarlow]

Jbalat, as an aside, my motor has been a real pain in far as it would cut out completely, no error on the diagnostics, just the whole unit would shut down. It is the latest X version of both the drive and BB. On the latest version of the firmware it would seem that if you have a speed sensor not working as in not recording speed, the motor will simply shut down without any error codes.

I think I have now found the cause, the magnet to sensor distance I set as per the TSDZ2 engine, a larger gap than you would expect on other systems. It seems that the Fazua system likes to be a lot closer. I had my bike upside down ( yes there is an error code for the bike being upside down ) peddling it and looking at the live diagnostics and I could see the speed ranging up and down quite randomly with some longer gaps at 0kph. I've moved the sensor closer and that seems to have fixed that issue. I've not yet been on a longer ride but the motor is still operating further than it has done along my nearby road.

Question is to you, is the motor cutting out as the speed sensor is not operating correctly. Fazua seem obsessed with restricting any use over 25kph to the point of irritating their client base. I had a technician from Germany link into my motor to try and find out whats going on with it and to reset the BB wheel circumference which comes from the factory as 7000mm. If the bottom bracket has this number then the motor is limited to 1500rpm which when first riding the motor you have to ask yourself why you bought it. Your local dealer cannot change the BB numbers unless he has your previously working BB that is registered at Fazua to you. Anyway the first thing he did was to change the speed limit from 26kph to 25kph, talk about being obsessive.

All Fazua needs to have is an error code for the cutting out from lack of speed sensor data, seems they forgot the obvious.

 

[Waynemarlow]

I've not yet been on a longer ride but the motor is still operating further than it has done along my nearby road.

Nope not yet fixed the problem, got as far as the first big hill and almost immediately cut out. Really starting to get a bit grumpy with this kit.

 

[benwilliam]

hi,
I have also a faulty fazua battery, I think it is the slightly newer version.
All Cells are fine and perfectly balanced, but the BMS refuses to charge.

Looking on the charge port, it allowes max 2A of charge current
and yeah I'm also wondering, there are only 2 wires, but the charger seems to have a 3rd pin, still don"t know what the 3rd pin is for.

here are some pics of my battery

 

[Ianhill]

Ive wondered why the 3rd pin on other stuff ive seen, mobility scooters do it and most the ebikes ive had too all had 3 pin xlr barrel on charger and battery but only the 2 wires terminated both ends total waste and used a crappy connector in the process.

Only thing i can think is cost and thats why the bms is so shoddy its bee designed by some school leaver for his university course work or something, for so many faluires im sure trading standards should be involved with some fit for purpose givin if it can be proved the bms is culprit.

I was inches away from getting a boardman with the kit but the frame was only medium so i didnt fit, thank to god i didnt £2000 for a bike thats just peddle is no joke.

I liked the look of the system for how compact it was and the way the bike behaves when flat closest to a normal bike with bottom bracket width etc i could live with low power im not looking for a free ride but that bms means the cheapest carrera is just as usable day to day in reality, shame as theres potential for a bike like this that works day in and out, for some this is a work ride and its not acceptable in my eyes for this to hit the shelfs.

 

[Waynemarlow]

I know we are getting outside of the original battery discussion somewhat, but aren't all Ebike batteries and also all EBike motors pretty marginal as far as reliability goes.

Certainly what I've seen of the Fazua design, its actually pretty well engineered, seems to do whats advertised on the tin, just its really really difficult to play with by the likes of ourselves. As I've already said, its a pay and play system, when it goes wrong, you give it back.

I'm not sure though Fazua is the only brand like this, Bosch and Brose certainly are the same.

 

[jbalat]

Hey Ben try contacting fazua before you do anything

 

[benwilliam]

Hey Ben try contacting fazua before you do anything

don't worry I did and I'm getting a new battery, so I can play around with the old one

 

[Waynemarlow]

Ben,

How did you contact Fazua, the Fazua agents are saying that as the battery is second owner, tough, Fazua have not replied to the Email I pinged off to their contact page. Admittedly your battery does look to be a later type.

Thanks