Can you build your own battery for the E10 ?

thaeber

Well-known member
Jan 26, 2021
888
769
Bruchsal, Germany
Hi Thaeber I have one empty box if you are interested .I bought it with the frame directly from Dengfu.But my friend who i am building the bike for, decided that he wants a battery with warranty and we bought a battery from Tossa.So if you are interested i can sell it to you for 50 Euro + shipping which is another 10 euro or so .

This offer is for everyone in Europe ;)

Greets

Sava
Thanks Sava, fair offer! But I already bought a second battery for my E10 some weeks ago, so currently no need!

Thomas
 

jtran69

Member
Jan 9, 2021
73
19
CA
Hello everyone. a new battery pack has arrived. 21700 13s2p 10ah 480wh, 2kg. smart bms. a rehearsal follows these days to see what the range is. the weight of the bike with this battery is great. 😀😀😀

View attachment 82261

View attachment 82262

Hi FICORAMA,
I hope that it is working out for you. Please update us on your new battery on range and perf especially when below 30%? 14s2p would fit too? Im very tempted to go this route.
 

ficorama

Active member
Oct 9, 2021
380
305
Croatia
Hi FICORAMA,
I hope that it is working out for you. Please update us on your new battery on range and perf especially when below 30%? 14s2p would fit too? Im very tempted to go this route.
greeting. range with 10ah battery with my m510 engine was max 33km and 1400m altitude. 10% of the battery left. below 50% the battery consumes faster than 100% -50%. mostly enough for some shorter rides.
 

patdam

Well-known member
Jan 17, 2019
904
602
france
greeting. range with 10ah battery with my m510 engine was max 33km and 1400m altitude. 10% of the battery left. below 50% the battery consumes faster than 100% -50%. mostly enough for some shorter rides.
interesting to know your weight and +- your physical level (how many D+ you can do without e-bike ?). Personally (+- 100 kg, able to do +- 600 D+ whitout e-bike) with BBS and 10Ah battery, upper than 1000 D+ i was worried about to empties the battery (arrived few time, the horror). i need at the less 14Ah to go serenely in mountain.
 

Waynemarlow

E*POWAH Master
Dec 6, 2019
1,126
902
Bucks
below 50% the battery consumes faster than 100% -50%. mostly enough for some shorter rides.
Don‘t confuse poor instrumentation with actual battery capacity, the modern cells we use typically the voltage falls quickly in the first 10% of use, then remains quite flat until the last 10% which falls really quickly.

It’s quite difficult for an instrument to read the voltage difference over that flat part of the discharge curve and hence we see comments like above by Ficorama. I’m not sure why more manufacturers don’t use Columb counting, that of counting max expected W/hs - used W/hs = a precise known how much oomph your battery has left.
 

ficorama

Active member
Oct 9, 2021
380
305
Croatia
Hi FICORAMA,
I hope that it is working out for you. Please update us on your new battery on range and perf especially when below 30%? 14s2p would fit too? Im very tempted to go this route.
yes, i didn't write. i am 90kg + cca 25kg bike. the ride was only on forest and mountain roads, quite steep climbs. mostly pass 2 and 3 on larger hills and pass4
 

jtran69

Member
Jan 9, 2021
73
19
CA
Ficorama,
Thank you for passing on the info and your experience! I notice that you're riding the M510. If you had the M500 before, would you do a quick comparision. My M510 is held up in the port of Shanghai/Shenzeng due to the shutdown :-(
 

ficorama

Active member
Oct 9, 2021
380
305
Croatia
Ficorama,
Thank you for passing on the info and your experience! I notice that you're riding the M510. If you had the M500 before, would you do a quick comparision. My M510 is held up in the port of Shanghai/Shenzeng due to the shutdown :-(
I posted a comparison. theme bafang m510. 6 or 7 page
 

Caio

Member
Apr 24, 2021
40
15
Sao Paulo Brazil
Hi Guys,

I’m also Building my own battery using the original case that fits to E10, when doing so, I became concern about the right Amps for my battery, my M500 is 48V and is labeled to work with 10ah, however when looking to this and other comments in this forum, it seems that the higher the amps provide the highest range? Is this correct?

When looking to the stock battery, it says that is 48v 17.5ah 840Wh (Dengfu provided), Is this really the case? Has someone tested to see if this is correct? I mean Chinese stuff are not always true to what is advertised….

Having said that, what is the optimal Amps for M500 48v? using the best firmware?

I appreciate your help and your comments,

Thanks

Caio
 

Waynemarlow

E*POWAH Master
Dec 6, 2019
1,126
902
Bucks
Hi Guys,

I’m also Building my own battery using the original case that fits to E10, when doing so, I became concern about the right Amps for my battery, my M500 is 48V and is labeled to work with 10ah, however when looking to this and other comments in this forum, it seems that the higher the amps provide the highest range? Is this correct?

When looking to the stock battery, it says that is 48v 17.5ah 840Wh (Dengfu provided), Is this really the case? Has someone tested to see if this is correct? I mean Chinese stuff are not always true to what is advertised….

Having said that, what is the optimal Amps for M500 48v? using the best firmware?

I appreciate your help and your comments,

Thanks

Caio
You’re asking some pretty “basic understanding of batteries “ questions that really you need to go and do a bit of homework research before embarking on this battery build project.

Perhaps the M500 / M600 thread maybe be better.
 

Tomteam

Member
Feb 18, 2022
22
19
Huelva. España
Hi Guys,

I’m also Building my own battery using the original case that fits to E10, when doing so, I became concern about the right Amps for my battery, my M500 is 48V and is labeled to work with 10ah, however when looking to this and other comments in this forum, it seems that the higher the amps provide the highest range? Is this correct?

When looking to the stock battery, it says that is 48v 17.5ah 840Wh (Dengfu provided), Is this really the case? Has someone tested to see if this is correct? I mean Chinese stuff are not always true to what is advertised….

Having said that, what is the optimal Amps for M500 48v? using the best firmware?

I appreciate your help and your comments,

Thanks

Caio
Hello.
You are mixing two concepts:
On the one hand those 10 Ah that the motor consumes and on the other the Ah that the battery is capable of supplying.
In theory, a 17Ah battery will be capable of operating for 1.7 hours. a motor that consumes 10Ah.
That's why it's not about what is the best? but what do I need?
Because the more capacity of the battery more weight and more space.
If you disassemble the battery, I would like to see the layout of the cells inside the box.
 

Seqlat

Member
Apr 18, 2021
49
17
PL/DE
battery built into the frame. battery weight 3.8 kg, length 38.5 cm, width 7.5 cm, height 7 cm. in place of the lock I installed a charging port

View attachment 80256
What's the range with your m510 engine on this 20ah akku?
Can you send what charging port you have installed in place of the battery lock? And what do you do with empty hole for charging port above the engine?

Does anyone know if the LG M50LT or M50L battery is a good option for the 13s4p and M510? Above 25C they give 7.3A

I don't know if the BMS should buy 30A or 25A if it gives 15A from 10-25C, and 7.3A above 25C, which gives not all of 30A in the case of normal use. I wonder what winter looks like when the package inside heats up but the external links do not exceed 25C
 

ficorama

Active member
Oct 9, 2021
380
305
Croatia
greeting. the longest ride I've done so far is 60km and 2000m in altitude. with the fact that a lot of driving was on asphalt. second ride all hardpack 50km 1200m altitude 25% battery, the terrain is great for driving wide fireroads. on forest roads and trails range depends on a lot. I say it all depends on the climbs, hardpack or dirt, the wind, the driver's mood and of course which pass you use. for me, on the same track, one ride consumes 20% dry terrain and the second ride 30% wet after rain. so there is no accurate estimate of the range. I hope it helped.
 

Seqlat

Member
Apr 18, 2021
49
17
PL/DE
greeting. the longest ride I've done so far is 60km and 2000m in altitude. with the fact that a lot of driving was on asphalt. second ride all hardpack 50km 1200m altitude 25% battery, the terrain is great for driving wide fireroads. on forest roads and trails range depends on a lot. I say it all depends on the climbs, hardpack or dirt, the wind, the driver's mood and of course which pass you use. for me, on the same track, one ride consumes 20% dry terrain and the second ride 30% wet after rain. so there is no accurate estimate of the range. I hope it helped.
Thanks for the answer. Can you tell us about the battery life in flat areas? I live in an area where the terrain is flat and a trip to the mountains is a weekend affair. And I wanted to ask again for the charging port used in place of the key.
 

ficorama

Active member
Oct 9, 2021
380
305
Croatia
Thanks for the answer. Can you tell us about the battery life in flat areas? I live in an area where the terrain is flat and a trip to the mountains is a weekend affair. And I wanted to ask again for the charging port used in place of the key.
unfortunately I can't say that. I don't drive on flat areas, I live near a forest, so I drive a few hundred meters on flat roads. 95% of my rides are forest and hill.
 

ficorama

Active member
Oct 9, 2021
380
305
Croatia
no, I put the charging port in place of the battery lock. i bought a 2pin port. the port needs to be adjusted, but it can be solved.
 

Aussie78

Member
May 11, 2022
47
49
Melbourne, Australia
Don‘t confuse poor instrumentation with actual battery capacity, the modern cells we use typically the voltage falls quickly in the first 10% of use, then remains quite flat until the last 10% which falls really quickly.

It’s quite difficult for an instrument to read the voltage difference over that flat part of the discharge curve and hence we see comments like above by Ficorama. I’m not sure why more manufacturers don’t use Columb counting, that of counting max expected W/hs - used W/hs = a precise known how much oomph your battery has left.

Man the price of a precision 50milliohm resistor and a LTC2944 is half of what these vendors want to buy a complete BMS for in 10k lots

IMG_5713.png
 

TeoElFeo

Member
Apr 13, 2022
185
63
Tallinn
A question to those who have experience with custom build batteries on 21700 cells. Do you think this batteries perform better then the stock one? Especially in the second half of the capacity? My stock battery doesn'seem to be doing great once the voltage drops to 45v and bellow. The sag is quite prominent even on lower PAS.

This is why I am considering getting a custom 13s4p or perhaps even a 14s4p soft case. I have m510 rev 1 and I am not 100% sure it will work with 52v, but there's a chance. The volt reading on the motor seems off and it shows 55.8 at full charge, but my multimeter shows 54.8. This makes me think the controller/fw doesn't really mind higher voltage as long as it's reasonable. I don't think that 52v will fry the controller because there are some firmwares for m510 rev 2 that are programmed for 52v. Please let me know what you people think of this?
 

Waynemarlow

E*POWAH Master
Dec 6, 2019
1,126
902
Bucks
Just get one of these built. At 780Wh and just over 3kgs, mine has been superb and I think for probably the first time, a set of cells may just exceed manufacturers specs. The M600 motor doesn't seem to mind the 58.8V's fully charged and together with short cranks makes a really good combo.

1666010312925.png
 

TeoElFeo

Member
Apr 13, 2022
185
63
Tallinn
Well, I'd like to squeeze in more if there's space and weight is not an issue for me. I know for a certainly it can fit 13s4p or even 14s4p so why stop at 13s3p(whish is more like 720wh)?

Also do you feel a noticeable difference in performance compared to stock battery?

When you say m600 doesn't mind 58.8 do you mean it is using 48v fw, not 52?
 

Waynemarlow

E*POWAH Master
Dec 6, 2019
1,126
902
Bucks
@Waynemarlow

I'm not picking holes, but can I ask what size wire you've used from the cells to the BMS? I usually use 12 AWG for anything up to 30A, yours looks a bit small but could be a deceiving picture.
Its 5mm2 ( equivalent 10AWG ) speaker wire. Why speaker wire, very high copper content with low impedance but still very flexible to wrap into tight corners if needed. Should be good safely to over 40 Amps but with 52 volts we should never see that.
 

ficorama

Active member
Oct 9, 2021
380
305
Croatia
for sale. greetings to all. I have 13s2p 10ah 21700 cells smart bms battery left. anyone interested in this battery? thank you
 

Aussie78

Member
May 11, 2022
47
49
Melbourne, Australia
Just get one of these built. At 780Wh and just over 3kgs, mine has been superb and I think for probably the first time, a set of cells may just exceed manufacturers specs. The M600 motor doesn't seem to mind the 58.8V's fully charged and together with short cranks makes a really good combo.

View attachment 99496

That pack is not suitable for ebike usage. The badly spot welded nickel strips are not going to hold it together. Cells from different groups are going to rub together, wear through the blue heatshrink sleeves and short out.

You need cell holders.
The spot welds on the negative end of the cells need to avoid the centre area, this is where the internal negative tab connects to the can.

The BMS floating about like that will quickly wear through the heat shrink and cause a short.

Whoever built this pack isn’t a mountain biker.
 
Last edited:

Waynemarlow

E*POWAH Master
Dec 6, 2019
1,126
902
Bucks
That pack is not suitable for ebike usage. The badly spot welded nickel strips are not going to hold it together. Cells from different groups are going to rub together, wear through the blue heatshrink sleeves and short out.

You need cell holders.
The spot welds on the negative end of the cells need to avoid the centre area, this is where the internal negative tab connects to the can.
The BMS floating about like that will quickly wear through the heat shrink and cause a short.

Whoever built this pack isn’t a mountain biker.
Cells from different groups are going to rub together, wear through the blue heatshrink sleeves and short out.
The cells are glued together with double sided sail tape. To be honest under the blue heatshrink is the negative can so even if there hadn't been glued tape between the cells, any break through would be negative to negative.

You need cell holders.
Sort of agree to get maximum dissipation of heat from the centre cells but as soon as you seal the battery to stop water ingress you get no air flow. Far better in my view to have as much cell contact to the outer protective cover which will then dissapate the heat. These batteries are way under there max amps anyway and heat is not really an issue.

The spot welds on the negative end of the cells need to avoid the centre area, this is where the internal negative tab connects to the can.
Correct but there are millions of homebuild batteries like this and largely without any issues.

The BMS floating about like that will quickly wear through the heat shrink and cause a short.
Again, the BMS is secured with double sided sail tape. Its not moving anywhere anytime soon. The biggest risk is from something on the bike wearing through the heat shrink if the battery was loose within the frame. But that is no more risk than than wiring on any frame getting worn through.

Whoever built this pack isn’t a mountain biker.
Not sure how you have worked that out. By all means you are welcome to go and buy manufactured batteries to suit your particular bike, its not a problem to me. You pay the premium, you pay the price of manufacturers support, you pay for manufacturers problems such as I've had on my EZesty batteries with having to buy a new over priced unit that was caused by poorly manufactured circuit boards.
 
Last edited:

EMTB Forums

Since 2018

The World's largest electric mountain bike community.

559K
Messages
28,288
Members
Join Our Community

Latest articles


Top