Can you build your own battery for the E10 ?

[Waynemarlow]

Yes is the answer, but with caveats here. The manufacturers use proprietory Can Bus signals and the likes to manage and interpret the battery to protect it from too much load and the total number of charges etc. But if you research and look around the internet its surprising how much info you can find. Do your research and you may well find for example that a few of us have built batteries for say the Bafang motors.


OK safety warning here, building batteries can be a risk to the builder. Why so, I am building 52 volt batteries which fully charged are 58.3 volts. Now anything around 60 volts DC with 15A of oomph behind it will stop hearts if you manage to get yourself in the wrong place and touch terminals you shouldn't, so beware, be safe and adopt good practice. If you want to see the tip of a metal screwdriver dissappear in front of your eyes then go prodding around one of these types of batteries, yes we all have done it once, but I can assure you it will be the only time.

OK why do I build batteries. Cost certainly, the battery below for £ 160.00 comes in at a pretty descent 780Wh's. Weight, that same battery is just over 3.0kgs, using the latest cells such as the Samsung 50E cells where each cell has nearly 5.0 amps of oomph compared to say the Samsung 30Q cells of only a couple of years ago with 3.0 amps. A 780 Wh battery of only maybe two years ago would have been pushing 4.0kgs. You get the picture, the batteries energy storage is becoming much denser. Learning curve, what a way to learn about the next generation of motorised transport until Hydrogen fuels take over.

OK so where and how, theres now a zillion articles and Youtubes on making Li Ion batteries for Ebikes but the best is probably a bed time reading session on Battery Technology - Endless Sphere and various Youtube feeds.

OK heres my latest

And how I have my 2 18650 x batteries paralleled into the Dengfu E10 I have giving me 680Wh usuable. The new 21700 above is more compact and quite a bit smaller in volume than the two batteries, I'm looking foward to getting it out and seeing what it will be like, its the first time we have used these high density cells.

 

[PadreParada]

Wayne, great post. Could you please tell us some more about the whole bulding process.

• Where did you order the Cells?
• Which BMS is best?
• How did you fit the battery into the Frame?
• etc....

Many thanks

 

[Waynemarlow]

Wayne, great post. Could you please tell us some more about the whole bulding process.

• Where did you order the Cells?
• Which BMS is best?
• How did you fit the battery into the Frame?
• etc....

Many thanks

Ok best two suppliers of batteries I have found are Fogstar Wholesale – The UK’s Number #1 Li-Ion Battery Supplier in the UK and Nkon.nl/ if you are in the EU. Nkon will also add tags to the battery, which then makes for an easy way of soldering the battery together, rather than having to purchase a spot welder. The first few batteries I built this way, are still going strong some 5 years later.

BMS's are funny things, you can pay a fortune or you can pay less than a fiver and get the same results. If they work from day one, they seem to work forever. I also spray all mine with conformal coating and then getting covered in water is not such an issue. I've almost given up on specifying a BMS as everytime you go to buy more, they are no longer in production or not available. Ebay is good for low volume and fast delivery, Ali Express is really cheap but takes about 10 - 14 days to turn up.

Best way to fit the battery to the frame is to simply use industrial velcro and simply mount the battery to the cover, the cover is pretty strong and when you remove the cover, the battery comes with it. Industrial Velcro always amazes me how much weight it can cope with.

But if you tally up the costs, for not a lot more you can get the Bafang battery, just it will weigh more.

 

[m.john]

Ok best two suppliers of batteries I have found are Fogstar Wholesale – The UK’s Number #1 Li-Ion Battery Supplier in the UK and Nkon.nl/ if you are in the EU. Nkon will also add tags to the battery, which then makes for an easy way of soldering the battery together, rather than having to purchase a spot welder. The first few batteries I built this way, are still going strong some 5 years later.

BMS's are funny things, you can pay a fortune or you can pay less than a fiver and get the same results. If they work from day one, they seem to work forever. I also spray all mine with conformal coating and then getting covered in water is not such an issue. I've almost given up on specifying a BMS as everytime you go to buy more, they are no longer in production or not available. Ebay is good for low volume and fast delivery, Ali Express is really cheap but takes about 10 - 14 days to turn up.

Best way to fit the battery to the frame is to simply use industrial velcro and simply mount the battery to the cover, the cover is pretty strong and when you remove the cover, the battery comes with it. Industrial Velcro always amazes me how much weight it can cope with.

But if you tally up the costs, for not a lot more you can get the Bafang battery, just it will weigh more.

Hi Wayne, great idea and helpful information.

What irritates me a bit is your starting post with the possible 'caveats based on the manufacturers use of proprietory Can Bus signals'. What does this mean exactly. Can I build my DIY battery within the motor spec and it will work or do I need a special tool like BESST or a special BMS to make the battery work with the rest of the CANBUS system.

Reason I am asking is that I try to build multiple 100Wh basic packs to parallel them together being able to take the 100Wh blocks on an airline. For sure not the state-of-the-art Amp monster when talking 48V but at least a chance to get an EMTB abroad.
If there is more knowledge required than a DIY battery I would appreciate a helpful link where I can find the required info. For the moment still waiting for the frame and initial Bafang set to arrive here.

Thanks in advance.
Martin

 

[Waynemarlow]

Martin, why the irritation with me ? Proprietory Can Bus signals are there for a reason, to give longevity to the battery, prevent mis use of the battery, give information back to the manufacturers so that they can support the buyers of their products, but with the cost to the buyer of cleaning out their wallet.

One has to remember the Bafang protocols are proprietry and we wouldn't want to publicly state otherwise , but I am lead to believe that with careful internet reading on other forums it is possible to power Bafang motors with batteries other than Bafang authorised kit.

As to your 100Wh batteries then you may want to think along the lines of splitting the voltages down into 12 volt lumps as in 4 packs to give you 48 volts ( sort of ). Something like 4S2P packs of Samsung 40E cells would give you what you are looking for but and its a big but, each set of 4 packs giving 400Wh would have to be charged together, electrically connected and electronically controlled somehow. Everytime you add wiring and electronics you increase the pack size and decrease the reliability.

In my view if you want to fly with batteries then it would be just far less hassle and cost to simply hire when you get there.

Just as an aside here is my latest 780Wh battery, very impressed so far and I think the quoted specs are what we are actually seeing in the field.

 

[Bogdan]

One has to remember the Bafang protocols are proprietry and we wouldn't want to publicly state otherwise , but I am lead to believe that with careful internet reading on other forums it is possible to power Bafang motors with batteries other than Bafang authorised kit.

Can you point us in the right direction

 

[m.john]

Martin, why the irritation with me ? Proprietory Can Bus signals are there for a reason, to give longevity to the battery, prevent mis use of the battery, give information back to the manufacturers so that they can support the buyers of their products, but with the cost to the buyer of cleaning out their wallet.

One has to remember the Bafang protocols are proprietry and we wouldn't want to publicly state otherwise , but I am lead to believe that with careful internet reading on other forums it is possible to power Bafang motors with batteries other than Bafang authorised kit.

As to your 100Wh batteries then you may want to think along the lines of splitting the voltages down into 12 volt lumps as in 4 packs to give you 48 volts ( sort of ). Something like 4S2P packs of Samsung 40E cells would give you what you are looking for but and its a big but, each set of 4 packs giving 400Wh would have to be charged together, electrically connected and electronically controlled somehow. Everytime you add wiring and electronics you increase the pack size and decrease the reliability.

In my view if you want to fly with batteries then it would be just far less hassle and cost to simply hire when you get there.

Just as an aside here is my latest 780Wh battery, very impressed so far and I think the quoted specs are what we are actually seeing in the field.

View attachment 54561

Thanks a lot for the feedback and sorry for the late reply.
I was worried that there is a protocol needed to run on DIY batteries. The limit seems to be the max (maybe even min) voltage not to trigger error codes.
To build my own batteries is not because its so super smart but for different purposes which might even require different modular concepts.

1. to respect the 'dangerous goods' airline regulation (100Wh no limit in units or 2x150Wh with airline approval) as long as there is no simpler way to ship to destination.
2. You can assemble capacity to your daily need. As said in other posts, if your trip barely uses 50% of the charge, why carry all the weight.
3. When using a M800 with lower requirements you will drop under 20kg and end in the light-EMTB class which might be interesting for riders not able (individual fitness) to ride with friends/kids anymore.

As the E10 frame geo does not allow to mount an external battery which you could rent abroad the modular concept might be the best if not willing to pay 300+€/week to rent an EMTB with unknown spec sheet. In general, airlines approve EMTB being checked in without battery.

It is always a balance of pros and cons what is best for your purpose and needs.
Thanks again for your reply and I'd appreciate some links to the 'careful internet reading on other forums' covering DIY batteries with Bafang motors. Just saving some time and energy, if you do not mind.
Martin

 

[Waynemarlow]

M.John. Bogdon, I’ll go back through some of the early enquiries I made on the battery section of Endless Sphere where I asked and researched how to make batteries and bring up some links, but in the short term why not simply go into the forum Battery Technology - Endless Sphere where having a good dig around is all part of the journey of doing something new. Perhaps just do a search on my user name in that specific part of the forum and many of my questions will be the same as yours.

There at least 2 possibly 3 posters here on this site who are running Bafang engines on self build batteries, perhaps they could chime in or at least PM you on their experience.

A question to you. Most importers of batteries use air freight to bring in large quantities of cells. All those cells are typically almost at the lower end of their charge and by consequence have little to no W/hs left in the battery. So have you researched actually what are the airline’s actual requirement ? If say you turned up with a series of inter linked cells but without charge, certainly less than 100 W/hs, would if the unit was marked as such with a professional looking calibration sticker, comply to their flight requirements ?

 

[Bogdan]

Waynemarlow - at battery pack I can see just + and - wires connected to BMS and further to Batteries. I cannot see any additional CAN electronic or connections. Did I understand wrong, that for M500/M600 motors you need some sort of additional connections/electronic to work with home made battery pack?

 

[Waynemarlow]

Waynemarlow - at battery pack I can see just + and - wires connected to BMS and further to Batteries. I cannot see any additional CAN electronic or connections. Did I understand wrong, that for M500/M600 motors you need some sort of additional connections/electronic to work with home made battery pack?

I personally are running a TSDZ2 engine and with the Freeware available we don’t need any of the Canbus connections. I had intended to fit a M500 but when I ordered my frame it was as yet unavailable so with a TSDZ2 engine sitting in my garage it was duly fitted. To be honest we’ve now done well in excess of 10K miles on 6 engines on 6 bikes in our group, in really severe U.K. conditions. These are hard working off road mtb miles doing on average 600 - 800 m of climb on every ride. Yes we’ve had a couple of water ingress related problems ( which we are learning how to deal with ), but there’s a wide range of cheap spares available and a brand new motor is only £ 275.00, do I really now want to bother fitting the M500 until it’s been sorted out, probably not.

Can I suggest you may want to read through the following thread and all the answers are there for you.

Bafang M500/M600 thread

Since this seems to be an interesting motor, why not have a separate topic for it? I'll start with three quotes I have found about the motor on this forum, feel free to add more information that you can find. Over the last couple of days I had heard that there had been reports of the M600...

endless-sphere.com

 

[Bogdan]

Thank you!
If you have a working product that covers your needs it make no sense to change it.

 

[m.john]

Also from my side, thank you for the info.
My intention is more a M500/800 combination. Smaller and modular batteries. But nothing too complicated.

 

[Fridgylife]

Hi I registered here for this thread. I have a couple of questions regarding the battery for the e10. I want to build a 14s pack with 21700 cells I was wondering if anyone has managed to fit these cells inside the frame. Does the original battery come with a BMS that talks to the motor controller?

 

[Waynemarlow]

Hi I registered here for this thread. I have a couple of questions regarding the battery for the e10. I want to build a 14s pack with 21700 cells I was wondering if anyone has managed to fit these cells inside the frame. Does the original battery come with a BMS that talks to the motor controller?

Ummm I think the whole thread started with a 14S3P 21700 pack.

 

[thaeber]

Could I use something like this?

 

[Waynemarlow]

Dimensions will tell you all, but at a guess in the 13S4P 21700 batteries it will be a no.

 

[thaeber]

Thanks! You mean from a size perspective (295 x 88 x 75) it will not fit? But in general, those packs are available in many sizes and capacitys. Is this a „plug and play“ solution, or is there anything to be adopted or changed?

 

[Waynemarlow]

Thanks! You mean from a size perspective (295 x 88 x 75) it will not fit? But in general, those packs are available in many sizes and capacitys. Is this a „plug and play“ solution, or is there anything to be adopted or changed?

There are so many variables outside of my own TSDZ2 engine, I can't really comment precisely enough to be able to say yes or no. Perhaps you may want to PM the likes of KaroKonig or patdam who are running the Bafang M600 with home built batteries. I also know there are others here on this forum doing so.

My Dengfu E10 with Bafang M600

www.emtbforums.com

 

[Bogdan]

M600 does not need special BMS - I got mine M600 last week and test it (on a table) with 48V battery and cheap BMS with just + and - connected.

Can someone measure maximum size that will fit in E10 frame?

 

[patdam]

M600 does not need special BMS - I got mine M600 last week and test it (on a table) with 48V battery and cheap BMS with just + and - connected.

Can someone measure maximum size that will fit in E10 frame?

An supplier have said me we can use basic BMS with M serial motor, but data displayed will be wrong.

 

[thaeber]

Looking for a more lightweight and smaller 2nd battery for shorter trips, I got an offer for a 14S2P pack, using the Samsung 21700 50E 5Ah or the 50G with a little less then the 10Ah of the 50E cells (4850 mAh each), but better lifetime and current balance under load, and they are much cheaper. What do You think?

 

[Waynemarlow]

if someone is selling you the 50E for Ebike duty in 14S2P format then you may want to ask questions on their suitability as a supplier or have you assumed as I used them in the 14S3P that they would be OK ? As I have already pointed out each individual cell call handle 10 amps, so we are now using 2 x giving 20amps max current. Now that may sound OK but I can assure you your motor will peak around that.

So we have whats called a 1 C situation which the battery boffins at Samsung have tested their battery in ideal temperature and drawoff circumstances would say thats OK. Out in the field however you will find things quite different and indeed in our use of the Samsung 35E batteries we got caught in the same scenario, they don't live up to spec in the field at 1C. We have found that in the last stages of charge the voltage sag at 1C is such that you will trigger the BMS early and you will have less over all power than the older 30Q batteries we had been using, which are rated much lower for capacity.

I would recommend that you go no lower than 2C or as I have done 1.5C ( 14S3P ) with these batteries, they work really well with the extra overall max rating of now 30 amps.

We have been using the Samsung 21700 40T which have a 35 amp 1 C rating in the 14S2P with really good success and out in the field they actually seem to exceed manufacturers specs. Top battery with an ability to hold good voltage levels until the bitter end.

 

[savas]

ny

Looking for a more lightweight and smaller 2nd battery for shorter trips, I got an offer for a 14S2P pack, using the Samsung 21700 50E 5Ah or the 50G with a little less then the 10Ah of the 50E cells (4850 mAh each), but better lifetime and current balance under load, and they are much cheaper. What do You think?

Hi Thaeber,
going the same road as you.14s2p same cells.The main concern is for me how to bring-attach the pack in the frame,so it does not move during rides and jumps.Any ideas?
Waynemarlow how is your custom pack attached?Any photos?

Greets

sava

 

[jcal]

What is the E10 battery dengfu ships? Is it a Bafang BT F25.820.C? something custom?

 

[Waynemarlow]

A simple + and - will power up the Bafang M600. You will not get some of the display features such as " range" but you soon learn what range your battery will do by using both the display and the Bafang App which will display volts.

The Samsung 50E 21700 cells as 14S3P at 780Wh's are definately a big thumbs up. Does seem to make the motor a bit fiesty until a volt has been dropped and then its back into the normal 48 volt battery range. I would suggest with this M600 motor to stick with the 48 volt battery it was designed for, its more than powerful enough.

 

[Hondy]

A simple + and - will power up the Bafang M600. You will not get some of the display features such as " range" but you soon learn what range your battery will do by using both the display and the Bafang App which will display volts.

The Samsung 50E 21700 cells as 14S3P at 780Wh's are definately a big thumbs up. Does seem to make the motor a bit fiesty until a volt has been dropped and then its back into the normal 48 volt battery range. I would suggest with this M600 motor to stick with the 48 volt battery it was designed for, its more than powerful enough.

Does anyone tried to make a battery for the E10 more then 840Wh ? Doing rides with 2 orginal batteries dengfy 100 to 120 km (M600) ...Like to do a bit longer distance (and more hm) in the future . If possible to make such a batt would be interresting to have ...,Not ever build one so thats the question to the experts (-: thx in advance .....Must say the M600 gooing quite well ,more then enough power ...i'm set at 1350km at the moment !

 

[Waynemarlow]

There is space with the 14s3P 21700 battery I built at either end and I think with careful battery construction and layout it could be possible to build a 13S4P battery but it would be very tight I would suspect as the frame is designed with 18650 batteries in mind.

A 14S3P Samsung 21700 50E battery will give you 780W\h’s
A 13S4P Samsung 21700 50E battery will give you 960W\h’s

Is it worth the cost and development for just 18% of additional battery ?

I’m only using about 550W/h’s on 1K of climb over 50K of quite knarly and slow off road, and would suspect that if I backed off a bit on power and had more open terrain, 100km would be possible on the 1 battery ?

 

[Hondy]

There is space with the 14s3P 21700 battery I built at either end and I think with careful battery construction and layout it could be possible to build a 13S4P battery but it would be very tight I would suspect as the frame is designed with 18650 batteries in mind.

A 14S3P Samsung 21700 50E battery will give you 780W\h’s
A 13S4P Samsung 21700 50E battery will give you 960W\h’s

Is it worth the cost and development for just 18% of additional battery ?

I’m only using about 550W/h’s on 1K of climb over 50K of quite knarly and slow off road, and would suspect that if I backed off a bit on power and had more open terrain, 100km would be possible on the 1 battery ?

Ok thats clear thx ...but 18% to the orginal batt is stil alot if the result is seen in the range ...wel the M600 consuming a lot in the first mode ...nothing todo about that ,but a 100km on 1 batt nooway sir !

 

[Sandur-Rx]

Wel, 960w would get you very close. I got 70km out of 650w battery. Lowest level on quite even ground.

 

[Hondy]

Wel, 960w would get you very close. I got 70km out of 650w battery. Lowest level on quite even ground.

Hello ,Nice To hear but hard to believe from a bafang M600 .Are we talking about the same motor ? I got max 70km(1 batt) on flat hardend roads with zero hm .on a dengfu batt 840Wh