Battery doesn’t charge beyond 84%

dodjaki

New Member
Hi,
I bought a Eunorau bike and when I charge it completely it reaches only 84%
During charging, red light is on.
end of charging: green light come on.
even after I leave it an extra hour on green light , it never charges beyond 84%
maybe the 84% reading is wrong.
has anyone the same experience ?
Is something wrong with the battery or the charger ?
Does any one have a solution for bringing the reading to 100%
thanks for your help.
 

rich c

Well-Known Member
Did you measure voltage with a multimeter? Knowing the exact voltage is necessary vs a percentage reading. Maybe they sent you the wrong battery pack. Like a 36v instead of a 48v.
 

Thomas Jaszewski

Well-Known Member
Did you measure voltage with a multimeter? Knowing the exact voltage is necessary vs a percentage reading. Maybe they sent you the wrong battery pack. Like a 36v instead of a 48v.
YES! How are you reading 84%? I never trust "indicators" best to actually MEASURE voltage! What is the rating on the charger?
 

Browneye

Well-Known Member
Check for a display setting for voltage - maybe it's set for 52v.
Or perhaps you got a 52v battery.

And yes, put a volt meter on the battery lead after a full charge - it should be close to the 54v full charge value. If so it would indicate an errant value on your display.

A 48v charger won't peak a 52v battery to its near 60v capacity.
 

harryS

Well-Known Member
You're not going to know until you get a voltmeter on the battery terminals. A 48V battery is 54.6 volts at maximum charge, and can be run down to around 40-42 volts at which point the bike controller will shut down.

The capacity is not linear. 85% means it's seeing 52.3 volts. 50% is around 47 volts. It's kind of silly, in my opinion, to assign a percentage to the battery capacity on a display. Better to to just show levels.

As for the charger, you can measure its no load voltage, which should be 54.6V. The way most chargers work, they sense when the battery is not drawing any further charge current and the LED flips to green. The final voltage does not have to be 54.6 when this happens. If it did shut off too low, leaving the charger connected will sometimes allow the battery to balance internally and increase the final voltage.

A brand new battery might be a little low, no more than 1 volt. Run it down, recharge it, and it should hit its max after 2 or 3 cycles. That's why you want to put a voltmeter on it and see if it really is 2 volts off and this is not due to a poorly calibrated display. If the display is off, just live with it. A replacement won't be any better,
 

Ebiker01

Well-Known Member
May be also if the charger is not connected directly into outlet.
When i have the charger into a surge protector with 2-3other devices(heater/ monitor, etc) the charger gives me issues also.
 

Thomas Jaszewski

Well-Known Member
It clearly reads 48V battery.

GREAT JOB on providing information!

As Harry mentions, only a multimeter or wattmeter will give an accurate voltage. Browneye's idea might also be a solution. I your settings are for a 52V battery.

In the end an inexpensive multimeter is the best tool for trouble shooting many eBike issues.
 

dodjaki

New Member
Bravo ! Bravo !
rich c, Thomas Jaszweski, Browneye, HarryS, Ebiker01
And thank you !
To rich c and Thomas Jaszweski :
Indeed, the multimiter voltage is 54.4 V
To Browneye :
Checked display settings for voltage: it’s 48 V , my battery is 48V
Battery lead after full charge is 54.4 V ( i.e., “errant value on display “ - thanks Browneye !
Indeed , my “48V charger doesn’t peak a 52V battery to it’s near 60V capacity “ ( thanks again Browneye ! )
To HarryS :
“Voltmeter on battery terminals is 54.4 V
Indeed like you say : “ 48V battery is 54.6V at full charge and can be run down to 40 - 42V “ thanks HarryS, useful lesson for me.I Iearn from you HarryS that the capacity is not linear : 85% means 52.3V ect... like you say : “ percentage on display has secondary value ( sometimes misleading )
The charger is indeed 54.6V at no load voltage.
also HarryS, thanks for your insight :
Quoting you : “a brand new battery might be a little low ... if I run it down , recharge it, it should hit its max after two or three cycles.
like you say : “ I would just live with a display that is off “
To Ebiker01 :
The charger is connected directly to outlet.
to Thomas Jaszweski :
My settings is set for 48V battery.
You guys are tremendous brains.
Wow !
Infinitely grateful for your help !
You made my new biking life !
 

thomasq

New Member
Hello dodjaki, My Eunorau bike does the same thing. BTN says the bike was programmed to a 52V battery and the bike comes with 48V battery.
BTN wants me to download software and change controller settings to a 48 V battery. Due to lots of steps and one of their files I unzipped had virus. I decided not to do this.
BTN says that a 52V battery will work for these settings. Have you tried this? I have not yet tried yet.
Have you fixed this issue yet?
Let me know what you have done or tried or going to do.
For me, I'm just riding my bike but getting only 15-18 miles to a charge.
Thanks!
 

Browneye

Well-Known Member
They would not send a file with a virus. You would turnoff AV software to load a tool for reprogramming. At least that would be my assumption.
It probably opens a port to send data and your AV software is picking up the activity.
 

Thomas Jaszewski

Well-Known Member
Hello dodjaki, My Eunorau bike does the same thing. BTN says the bike was programmed to a 52V battery and the bike comes with 48V battery.
BTN wants me to download software and change controller settings to a 48 V battery. Due to lots of steps and one of their files I unzipped had virus. I decided not to do this.
BTN says that a 52V battery will work for these settings. Have you tried this? I have not yet tried yet.
Have you fixed this issue yet?
Let me know what you have done or tried or going to do.
For me, I'm just riding my bike but getting only 15-18 miles to a charge.
Thanks!
Again, there is no program setting that would prevent a 48v battery from working and only allow a 52v battery.
 

dodjaki

New Member
Hello Thomasq,
Although the bike is programmed for a 52 Volt battery, I decided to live with a 48 Volt battery.
it’s intimidating for me to download software and change controller settings to 48 V
I am not computer literate, I fear to mess up something.
I also get 15 miles autonomy. I rarely ride farther.
I wish you success in your trying Software.
I am guessing that if the current 48 V battery gets old it will be possible to replace it with a 52 V
Or wait till we have enough confidence and bravery to adopt a quicker remedy.
please let me know if you find an answer that gives positive results.
wishing you enjoyment with your new bike.
 

Thomas Jaszewski

Well-Known Member
Hello Thomasq,
Although the bike is programmed for a 52 Volt battery, I decided to live with a 48 Volt battery.
it’s intimidating for me to download software and change controller settings to 48 V
I am not computer literate, I fear to mess up something.
I also get 15 miles autonomy. I rarely ride farther.
I wish you success in your trying Software.
I am guessing that if the current 48 V battery gets old it will be possible to replace it with a 52 V
Or wait till we have enough confidence and bravery to adopt a quicker remedy.
please let me know if you find an answer that gives positive results.
wishing you enjoyment with your new bike.
Do you have a Bafang mid drive? Depending on when you bought it, it could have firmware that won’t allow it to run a 52v battery. Fixing that is not the same as what is called programing the controller. Firmware changes are much more difficult.
 

dodjaki

New Member
Yes, I have a Bafang mid drive.
I bought it in October 2019.
I don’t know if my firmware will allow it to run a 52 V battery.
if my firmware won’t allow me then I will renounce.
I have no problems with 48 V
This isn’t a must as the distance range is not critical.
like I mentioned, as I am shy of meddling with software, I rather play it safe and be contented with what’s available and with the existing situation.
As concerning you Thomasq, you might have different ambition.
And hopefully your firmware will be cooperative and friendly.
I wish you success.
Please let me know when you find an exciting discovery.
 

thomasq

New Member
Good to hear from you dodjaki/ThomasJ.
dodjaki. I'm with you when downloading software and making changes to controller. I have a son that's a programmer that was going to help me. He was able to get on my computer from 2000 miles away and suggested downloading a virtual drive to make changes and deleting virtual drive when finished due to potential virus. He even had questions on all the steps needed to make changes on the controller. Thats when I decided to go back to BTN for another option. Or talk to someone that has same issue that has performed software download and successfully made changes to controller. So far I have not found anyone.
BTN has told me that a 52V battery will work and show 100% when fully charged. But anything BTN tells me, I cannot trust them anymore. I was going to buy more bikes from them but I will never do that now. There customer service is bad, they ask for order # and act like they don't know me, their warranty means nothing, they don't want to spend money to fix customer issues. I'm not sure how they will be successful in USA when customer service is everything.

ThomasJ, you've ask me to check voltage at 50%/25%/10%, I can do that but not sure what this would accomplish. As dodjaki said, were only getting 15 miles on a charge.
Once the bike gets down to 20% and your trying to go up steep hill and you use 5 assist level the bike will struggle and sometimes the battery will go to 0 on display and then you will have no assist. This is when I will put bike in 3 or 4 assist and the bike will settle out.

Its unfortunate because I'm charging my bike after every ride. Even a ten mile ride.
I was hoping to find someone that's used a 52V battery with success.
This is my next step. Another $500 dollar cost. In 2/3 weeks I'll get battery and I'll post with update.

Yes, I too have a Eunorau mid drive. Buyer Beware!!!

Display:
 

Thomas Jaszewski

Well-Known Member
Good to hear from you dodjaki/ThomasJ.
dodjaki. I'm with you when downloading software and making changes to controller. I have a son that's a programmer that was going to help me. He was able to get on my computer from 2000 miles away and suggested downloading a virtual drive to make changes and deleting virtual drive when finished due to potential virus. He even had questions on all the steps needed to make changes on the controller. Thats when I decided to go back to BTN for another option. Or talk to someone that has same issue that has performed software download and successfully made changes to controller. So far I have not found anyone.
BTN has told me that a 52V battery will work and show 100% when fully charged. But anything BTN tells me, I cannot trust them anymore. I was going to buy more bikes from them but I will never do that now. There customer service is bad, they ask for order # and act like they don't know me, their warranty means nothing, they don't want to spend money to fix customer issues. I'm not sure how they will be successful in USA when customer service is everything.

ThomasJ, you've ask me to check voltage at 50%/25%/10%, I can do that but not sure what this would accomplish. As dodjaki said, were only getting 15 miles on a charge.
Once the bike gets down to 20% and your trying to go up steep hill and you use 5 assist level the bike will struggle and sometimes the battery will go to 0 on display and then you will have no assist. This is when I will put bike in 3 or 4 assist and the bike will settle out.

Its unfortunate because I'm charging my bike after every ride. Even a ten mile ride.
I was hoping to find someone that's used a 52V battery with success.
This is my next step. Another $500 dollar cost. In 2/3 weeks I'll get battery and I'll post with update.

Yes, I too have a Eunorau mid drive. Buyer Beware!!!

Display:
Well I’m trying to assist and methodically review what’s happening. I do support for a company selling BBSxx motors. I’m thinking I might be ahead on the knowledge base. Free support, but I’m just as happy to walk away. Your choice.
 

thomasq

New Member
ThomasJ, Your support is always welcome. Your much more knowledgeable in this field and these issues.
ThomasJ. The real issue is BTN not supporting this issue. Why am I trying to find solution. I gave up trying to fix this issue with BTN on Alibaba.
Do you have affiliation with BTN?
It seems you never bring up the company BTN and they should warranty and fix issues for their products they sell.
The real issue is BTN.
They sold me a brand new bike that only gets 15 miles.

They do not warranty their product.
This is a brand new bike and they will not fix this.
BUYER BEWARE!!!
What company do you represent? That sells BBSxx motors. Maybe I buy my next bike from them?
 

Thomas Jaszewski

Well-Known Member
ThomasJ, Your support is always welcome. Your much more knowledgeable in this field and these issues.
ThomasJ. The real issue is BTN not supporting this issue. Why am I trying to find solution. I gave up trying to fix this issue with BTN on Alibaba.
Do you have affiliation with BTN?
It seems you never bring up the company BTN and they should warranty and fix issues for their products they sell.
The real issue is BTN.
They sold me a brand new bike that only gets 15 miles.

They do not warranty their product.
This is a brand new bike and they will not fix this.
BUYER BEWARE!!!
What company do you represent? That sells BBSxx motors. Maybe I buy my next bike from them?
I don’t sell here. I think there’s a chance there is an easy solution. Your posting detailed answers for Harry S ,myself, and others may be enough to help. Or just continue calling out BTN. Whatever..
 
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Hi, guys. Please find the place where you order the bike. BTN is a company who work with distributors only, they have been offer support to the distributor or dealers, so end user can get the solution from the bike where you purchase.