New battery for BH EMotion Neo causing battery level display problem

#1
We have a BH EMotion Neo City and a Neo Cross purchased new in 2014, and have now each travelled 2,900kms on them. They have been very good bikes for most of that time. Both handlebar controller connectors caused errors early on and were changed under warranty. The torque sensor got dirty on the City and caused it to launch off without a rider a couple of times in France this year. A bit alarming but solved by washing and drying the sensor.
The 12ah (11.6ah) Neo Cross battery is still good but the 9ah Neo City battery started failing this September and wouldn’t power either bike up hills in Cornwall. Both bikes cut out and powered down under load with the 9ah battery at half charge on the hill up to Heligan but would happily climb the same hill with the 12ah battery at a similar charge level. Conclusion:- the 9ah battery has failed.

Both battery packs are probably beyond their best. The bikes are five seasons old. Our choice was therefore between junking the bikes and buying two more (we have two electric Bromptons but they are only useful on roads) or replacing the batteries. We decided on the latter and are also replacing both handlebar connectors which had cracked. Total cost just less than £1,400.

The parts arrived from BH via a dealer last week. The battery decals match the existing ones. Both batteries are now 11.6ah so there will be no need to swap them at half distance when the City would be down to two bars whilst the Cross still had four.

The new batteries have a problem though. When fully charged overnight, fitted and locked to the bike and powered up, the battery display on the handlebars shows the charge level but every 10 seconds the battery icon flashes empty twice for a second and then goes back to the correct level. Both new packs behave the same way on both bikes. This is not a loose electrical connection. It happens continually and at precisely 10 second intervals. The battery icon always flashes twice before returning to full.

The dealer supplying the parts (not the dealer who supplied the bikes - they don’t handle BH anymore) says that they have seen something like this with a new 36v pack purchased for another older BH bike when they tested it on their diagnostic rig. They say it did not cause operating problems and that the power to the motor did not cut out. BH are aware of the issue but have no solution.

The implication is that all newly manufactured batteries to fit older BH Emotion models will cause the controller battery icon to flash/blink twice every 10 seconds but that it is “cosmetic” issue, not a functional issue.

I can’t do any real testing for a while as I am post-operative.

What do you think? Has anyone else seen this? Did it cause any problems?
 

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bob armani

Well-Known Member
#2
FYI- I have the 2015 Evo Jet and after countless power interruptions while using the side mount display, I went ahead and upgraded to the center 'heads up' display for a few dollars more from my dealer. I tried working the contacts on the back which became sticky after extended usage and were not making proper contact causing comm errors. After the upgrade, errors basically disappeared. I have also had issues with a dirty TMM4 torque sensor and was recommended an electronics spray (safe for plastics) and those problem (false positive errors) disappeared as well.
I think BH has a bad design for the side mount IMO. Too delicate to be used (while changing PAS levels) while riding. Center display is a better well built unit for these bikes. BTW-Still using the same battery. Good Luck!
 
#3
Thanks Bob.

I thinks you’re right that the side display is a design weakness. I like being able to change power levels with my thumb to either save power or get out of trouble quickly though. I certainly miss it on the Brompton folding electrics - I went off the side of the road on my second ride trying to change power levels.

I think the 9ah battery may have failed because it was always being depleted more or more quickly than the 12ah. I never ran flat and was always recharged immediately.

The original 12ah still seems fine but my goal now is to keep both bikes (“his and hers”) in sync as far a longevity. I don’t imagine that BH will be producing these proprietary battery packs in another 5 year’s time and I do regard them as consumables, albeit expensive ones.

I wonder how many people opt to scrap their ebike after 5 years rather than pay 1/3 of original price for a new battery? And how many attempt to re-cell rather than buying a manufactured pack? There must be other threads here on this so I’ll go looking.
 

bob armani

Well-Known Member
#4
Thanks Bob.

I thinks you’re right that the side display is a design weakness. I like being able to change power levels with my thumb to either save power or get out of trouble quickly though. I certainly miss it on the Brompton folding electrics - I went off the side of the road on my second ride trying to change power levels.

I think the 9ah battery may have failed because it was always being depleted more or more quickly than the 12ah. I never ran flat and was always recharged immediately.

The original 12ah still seems fine but my goal now is to keep both bikes (“his and hers”) in sync as far a longevity. I don’t imagine that BH will be producing these proprietary battery packs in another 5 year’s time and I do regard them as consumables, albeit expensive ones.

I wonder how many people opt to scrap their ebike after 5 years rather than pay 1/3 of original price for a new battery? And how many attempt to re-cell rather than buying a manufactured pack? There must be other threads here on this so I’ll go looking.
WonkyBass, Very good points. I think re-cell may be the only option as you have stated after 5 years. I have priced that out and they are about the same cost as factory batteries, however you can get better longer lasting cells for replacements which is an added bonus. Even if I get a good solid 5 years of riding from the bike, I feel it has paid for itself on many levels of enjoyment and staying fit. I think I will be ready for another BH or something similar. I think they make a very good and well built product.
 
#5
My eye is healing faster than the one operated on last year so I took a new BH batteries out for a 10 miles run yesterday. It seems fine other than the display level zeroing every 10 seconds. No power fluctuation.

Thinking about what the dealer told me, they tested a replacement 36v BH battery on a diagnostic rig and saw the voltage going to zero and back. So this is not incompatibility between the 5 year old bikes and the new.batteries. The batteries display this behaviour on their own from the factory, which is a bit annoying. But it does appear to be something I can just ignore.

Is the BMS in the battery effectively a computer? Does it sample the battery voltage at 10 seconds, store usage data and make decisions on charging regimes etc.?

I rail against deposing of functional items because of component failure, built-in obsolescence and all that. I want the tech I have to just keeping running happily for as long as possible. All our tech will end up as scrap one day, we’re discussing at what point this seems reasonable to us.

Having typed this and then discussed it with my wife, I now think your approach is probably more sensible than mine and our bikes have been fully amortised. I just find the thought of scrapping them unpleasant.
 

bob armani

Well-Known Member
#6
My eye is healing faster than the one operated on last year so I took a new BH batteries out for a 10 miles run yesterday. It seems fine other than the display level zeroing every 10 seconds. No power fluctuation.

Thinking about what the dealer told me, they tested a replacement 36v BH battery on a diagnostic rig and saw the voltage going to zero and back. So this is not incompatibility between the 5 year old bikes and the new.batteries. The batteries display this behaviour on their own from the factory, which is a bit annoying. But it does appear to be something I can just ignore.

Is the BMS in the battery effectively a computer? Does it sample the battery voltage at 10 seconds, store usage data and make decisions on charging regimes etc.?

I rail against deposing of functional items because of component failure, built-in obsolescence and all that. I want the tech I have to just keeping running happily for as long as possible. All our tech will end up as scrap one day, we’re discussing at what point this seems reasonable to us.

Having typed this and then discussed it with my wife, I now think your approach is probably more sensible than mine and our bikes have been fully amortised. I just find the thought of scrapping them unpleasant.
Yes, I agree with your statement 'the thought of scrapping them is unpleasant'. It is a beautiful piece of machinery indeed. Just keep it as an art piece under lights instead of putting in the junk yard to recycle is my best thought right now. Peace!
 
#7
Anyone else who decides to purchase new battery packs from BH for their older vintage Neo City, Cross etc. should be aware of another difference from the originals. The packs now seem to include Deep Sleep mode.

If you are not aware of this you will, as I did today, take your stored battery out and lock it onto your bike for the first time in over a month and wonder why it refuses to power up. You may wonder if all the charge you left in there (80% in this case) had leaked away in the intervening 30 days and wished your good old battery was still up to the job and that you had never spent so much on this rubbish new one (two in my case, City and Cross). This would all be a mistake! Your battery now has a BMS that goes into a protective deep sleep mode after (variable) periods of activity and can woken up by putting the battery on charge for 5 seconds.

There is nothing that came with the batteries or written on them about the new, Deep Sleep behaviour. The dealer who supplied the batteries has since sent me the following extract from a BH manual. It’s not clear if these intructions apply specifically to my batteries but they seem to fit in with the tests I did whilst trying to understand the problem. There are no State Of Charge button or displays on these batteries, which further suggests that these are generic BH instructions: -

“Stand By Mode

In order to minimise internal consumption, the battery automatically switches to Stand By mode. This happens automatically when the system detects no charging, no discharging and no communication with the battery for a period of 10 minutes. So, for example, this mode will automatically turn off the display panel after 10 minutes without use, if the user has left it on after parking. The user can exit this Stand By mode by simply turning on the bicycle's display panel.



Deep Sleep Mode

In order to protect the battery during long periods of inactivity or storage (for example, during the winter), the battery automatically switches to Deep Sleep mode. This happens automatically when any of the following situations occur:

• If the charge level of the battery is below 1%, the battery goes into Deep Sleep mode when the battery has continuously been in Stand By mode for 10 minutes.

• If the charge level of the battery is below 10%, the battery goes into Deep Sleep mode when the battery has continuously been in Stand By mode for 48 hours.

• If the charge level of the battery is below 40%: Deep Sleep mode is activated when the battery has continuously been in Stand By mode for 14 days.

• If the charge level of the battery is below 80%: Deep Sleep mode is activated when the battery has continuously been in Stand By mode for 30 days.



The user can exit this Deep Sleep mode by holding down the battery's State Of Charge button (which checks the charge level) for 5 seconds or starting to charge the battery with the charger.
 
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#8
The text about Deep Sleep mode appears in a BH Atom manual online. The same manual mentions some temperature sensing features that prevent battery discharge below -20c and recharging below 0c. Whether any or all of these features are built into the BMS for Neo batteries produced today is unknown.
 

bob armani

Well-Known Member
#9
The text about Deep Sleep mode appears in a BH Atom manual online. The same manual mentions some temperature sensing features that prevent battery discharge below -20c and recharging below 0c. Whether any or all of these features are built into the BMS for Neo batteries produced today is unknown.
WonkyBass-Thanks for posting. I found this out the hard way after long storage and finding the battery would not respond. The battery is off the EasyGo series BH bikes that slides onto a rear bracket located at the back of the saddle. The battery is the older version from a 2016 model. My other 36V 11AH battery for my other BH bike does not appear to have the deep sleep feature.
 
#10
I have a 2013 Jumper. Like you (My wife has a Jet 12amp battery) that I use. Ride every day and the display turned off at 2 bars on the original 9amp Full charge does the same thing no flashing the display off although the bike runs OK. Using My wife's battery shows no problems I have decided to have ebikemarketplace in Las Vegas rebuild my battery to 14amps for 600.00