New Battery problems

[Harry. B]

Hi guys.
Really have issues with my bike at the moment. I have an Australian stealth bomber B52 which I’ve owned for around 2 years now. I’ve had nothing but problems with my bike to be honest so I’ve slowly learnt from the beginning on how to fix them. I’m currently on my third motor and now my third controller.
I upgraded my original controller to a sabvoton SVMC72200 - APT 200A and it worked great for a while. Eventually my controller broke and I found out it had a short circuit between the live and negative lines. I originally thought it was the battery so I ordered a new 72v 28AH Sonyacells battery for £1200. When I plugged it into the controller there was a large spark and black at the terminals now very hard to connect and disconnect.

So I then ordered another controller after this and everything now works. But when I took it out for the first spin after giving it some heavy acceleration the whole bike shut off and no power at all until I disconnect and reconnect the battery. I’ve tried it a few times now and the same result (No Good )

I believe that the short circuit from the old controller has damaged the BMS system of the new battery which is such a let down. I am currently stuck for what to do now, what are you guys’ thoughts??? Any help much appreciated

 

[soundwave]

that's called voltage sag as when you want max power the cells cant keep the voltage high enough and the hole bike shuts down.

where did you get the batt from ?

 

[Harry. B]

that's called voltage sag as when you want max power the cells cant keep the voltage high enough and the hole bike shuts down.

where did you get the batt from ?

Ah I see. So not a damaged BMS?
I got it from https://electrobikeworld.com/products/stealth-bomber-72v-28ah-lithium-ion-battery
Which I thought was quite cheap at £1100

 

[soundwave]

those cells are about 7-10 quid each so it is cheap but its not like 400 quid either, can you half the amps coming from the pack and see if it still does it as if it does means a cell bank has a problem or a cell has gone bad.

do you have any warranty ? as going any further will mean striping the pack to the bms and checking the voltage for each cell bank via the balance connector on a multi meter.

 

[soundwave]

eBike Batteries

ebikebatteries.co.uk

Scott
Torque-E-Cycles
139 Bibbacombe Rd
Torquay
01803 325945


both build custom packs to any size but it wont be cheap!

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[Harry. B]

those cells are about 7-10 quid each so it is cheap but its not like 400 quid either, can you half the amps coming from the pack and see if it still does it as if it does means a cell bank has a problem or a cell has gone bad.

do you have any warranty ? as going any further will mean striping the pack to the bms and checking the voltage for each cell bank via the balance connector on a multi meter.

I will try that tomorrow for sure. Yeah I do have warranty, only thing is it’s from the US which is annoying. I wish I had of known where to go for quality battery’s before haha. I’m using a qs205 5000w motor which does take some power. My old battery worked really well with it.
I knew the battery wasn’t right, they’ve used 12 AWG cable which I thought was very thin.

 

[soundwave]

uk power cable is 13a at 3000w and ur pulling way more than that thin cables will just melt id contact the seller and tell them they sold you a batt with cells that does not match the cont output that motor and controller wants and if it did not cut out it will explode and melt down the bike frame with it.

sending that thing back over seas is not going to be a option as it will cost a fortune even if you can find some one to post it as most wont touch batts esp one of that size.

the first bikes i looked at was one of those but the 10k price tag the total waight of it and expensive batts means it would be next to useless on steep black red down hill tracks.

sell it get a bafang hd use the controller you have give it 45a with a 48-52v batt and a bike that will be under 25kg fs all done.

btw you can get 20kw hub motors but that makes the problem 3 times worse and even more waight, i can sprint with 500w from my legs in 10 years not 1 road bike can pass me with my tiny bosch cx motor with a dongle

Single Stage Big Block Middrive- RHD

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Experience ebikes and emountainbikes like never before with the CYC mid-drive conversion kits. High power, torque sensing, and complete control. From 250W to 5000W, we've got you covered with the X1 Pro, X1 Stealth, and Photon solutions. Turn any bike into an ebike!

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Wild-OX Bafang M500 M600 Mid Drive Downhill Dual Suspension Electric Bike Frame With Motor and Shock

Color: Black Material: Aluminum Alloy Set Includes: Frame Item Length: 940cm Brand: Risunmotor Manufacturer Warranty: 1 Year Part: Electric Bike Frame Item Height: 22cm Suitable Rear Shock Size: 200mm Compatible Bike Type: Bafang

www.risunmotor.co.uk

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Bafang description

bafang-e.com

 

[Harry. B]

uk power cable is 13a at 3000w and ur pulling way more than that thin cables will just melt id contact the seller and tell them they sold you a batt with cells that does not match the cont output that motor and controller wants and if it did not cut out it will explode and melt down the bike frame with it.

sending that thing back over seas is not going to be a option as it will cost a fortune even if you can find some one to post it as most wont touch batts esp one of that size.

the first bikes i looked at was one of those but the 10k price tag the total waight of it and expensive batts means it would be next to useless on steep black red down hill tracks.

sell it get a bafang hd use the controller you have give it 45a with a 48-52v batt and a bike that will be under 25kg fs all done.

btw you can get 20kw hub motors but that makes the problem 3 times worse and even more waight, i can sprint with 500w from my legs in 10 years not 1 road bike can pass me with my tiny bosch cx motor with a dongle

Single Stage Big Block Middrive- RHD

The best value in a high performance mid drive kit

lightning-rods10.mybigcommerce.com

AM Racing AMR 250-90 Single AC Motor - Liquid Cooled, Permanent Magnet - Remy Cartridge, EV West - Electric Vehicle Parts, Components, EVSE Charging Stations, Electric Car Conversion Kits

Supreme eBike Mid-Drive Conversion Solutions | cycmotor

Experience ebikes and emountainbikes like never before with the CYC mid-drive conversion kits. High power, torque sensing, and complete control. From 250W to 5000W, we've got you covered with the X1 Pro, X1 Stealth, and Photon solutions. Turn any bike into an ebike!

www.cycmotor.com

Wild-OX Bafang M500 M600 Mid Drive Downhill Dual Suspension Electric Bike Frame With Motor and Shock

Color: Black Material: Aluminum Alloy Set Includes: Frame Item Length: 940cm Brand: Risunmotor Manufacturer Warranty: 1 Year Part: Electric Bike Frame Item Height: 22cm Suitable Rear Shock Size: 200mm Compatible Bike Type: Bafang

www.risunmotor.co.uk

Home

Bafang description

bafang-e.com

I totally agree, to be honest I should of just got a surron but I went for the stealth as it looks more road legal haha. Nothing but problems, also have two hairline cracks in the frame so they just not worth the money.
Yeah I think I’ve been as good as scammed, I’m just not clued up enough and make mistakes. Thanks for all the help, I’ve learnt a lot!
ill let you know how it goes tomorrow

 

[Harry. B]

I totally agree, to be honest I should of just got a surron but I went for the stealth as it looks more road legal haha. Nothing but problems, also have two hairline cracks in the frame so they just not worth the money.
Yeah I think I’ve been as good as scammed, I’m just not clued up enough and make mistakes. Thanks for all the help, I’ve learnt a lot!
ill let you know how it goes tomorrow
Btw I meant the cable thickness coming out of the battery is very thin , it has an 80AMP BMS System (apparently)

 

[soundwave]

your not the first and wont be the last with batt problems on heavy bikes that need massive amps but when at this size and voltage its not worth the risk of burning ur house down.

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8, Adjustable rear dropout: it fits 150mm-170mm rear dropout hub motor. So it can be installed on both 26x 2.6", 26 x 3.0" & 26" x 4.0" wheel Bike. Want to have a cool Stealth Bomber Electric Bike?. 3, The battery casing: 330 x 202 x 140mm.

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id also forget a surron with those kids getting killed because they had no fkn crash helmets on even seen a kid today on back of moped flying down the road going 50mph and he had his hood up for protection

plus those batts are like 2k what i want is a bike that's 15kg can go 50mph for 50 miles fat out, we aint there yet

 

[Harry. B]

your not the first and wont be the last with batt problems on heavy bikes that need massive amps but when at this size and voltage its not worth the risk of burning ur house down.

E Bike Frame bicycle Frame 150-170mm dropout for Stealth Bomber Electric bike | eBay

8, Adjustable rear dropout: it fits 150mm-170mm rear dropout hub motor. So it can be installed on both 26x 2.6", 26 x 3.0" & 26" x 4.0" wheel Bike. Want to have a cool Stealth Bomber Electric Bike?. 3, The battery casing: 330 x 202 x 140mm.

www.ebay.co.uk

id also forget a surron with those kids getting killed because they had no fkn crash helmets on even seen a kid today on back of moped flying down the road going 50mph and he had his hood up for protection

plus those batts are like 2k what i want is a bike that's 15kg can go 50mph for 50 miles fat out, we aint there yet

Just set it to half dc current (75A) and runs just fine. Went for like a 6 mile ride and had 79V when I got back, the battery indicator was still on 100% which is odd. Isn’t 5v a significant drop for only a 6mile ride with a 28Ah battery.
Thanks again for all the help. seems the battery just isn’t good enough. But atleast it works for now haha might see how it goes on 100A

 

[soundwave]

id go up 5-10a at a time as the bms is cutting out for a reason plus the pack will last longer the less you hammer it esp if you want rid of it

 

[Harry. B]

id go up 5-10a at a time as the bms is cutting out for a reason plus the pack will last longer the less you hammer it esp if you want rid of it

Ive got it up to 90A and running great. Not as much of a let down as I thought. Im happy enough with this power, it’s not what it was before but still good enough. I guess that’s what you get when you don’t spend £2000. I can’t help but go fast haha. It’s not gonna blow is it haha. Atleast I can ride again, finally can’t thank you enough

 

[soundwave]

imo the bms was cutting out because it was getting to hot but if you can run it at 90a and heat is not a problem then it should be ok but check the temps esp on hot days.

more amps means less range and the pack will loose its capacity faster.

 

[Harry. B]

imo the bms was cutting out because it was getting to hot but if you can run it at 90a and heat is not a problem then it should be ok but check the temps esp on hot days.

more amps means less range and the pack will loose its capacity faster.

Yeah will keep an eye on it thanks