Replacing battery

#21
I opened the pack and I can't find anything wrong. In fact, I have measured between pads in the packs and all were giving around the same volts (range of differences is within +/-0.05 volts, so it seemed pretty well).

When charging, I don't disconnect the charger immediately. I keep the bike in a storage room out of my flat, so I leave it charging for hours or even days, so in case a prolonged charge would help to balance cells, that would have already happened.

What seems to improve the behavior is to discharge the battery slowly (with a resistance -ie; a heater-). I make it go below the point where the led scale does not show any led lit. I stop around 32V cause I'm afraid of over-discharging, even when it is expected the BMS won't allow such over-discharge. A charge after that takes significantly longer, and doing that last weekend, I did a 45 Km route without any issue. Not sure if it has any explanation (like discharging overcharged -unbalanced- cells, and then the following charge will balance the pack) or it was just a lucky day.

My ideal situation is the battery may show signs of aging in the sense of shorter range, but at least does not power off. I understand a battery with 9000Km on it (after 3 years of usage) may have lost a significant capacity percentage, but what puzzles me is the battery stops completely at random.
 

J.R.

Well-Known Member
#22
Battery issues are often the one big annoyance with ebikes. To add to the knowledge base of this thread, I have a '15 Evo (36v, 417wh) and I just purchased a new battery from my dealer in Wisconsin last summer. It was 35% less than the cost noted above and that included shipping from BH headquarters in St. Louis to Pennsylvania. I wrote about the purchase in this thread.

To me the cost was worth it, the bike is still great, original pack gets ~35 to 40 miles in eco. If it was a grand plus s/h and tax, I'd have thought twice about it. I guess the price could have gone up since the summer. Also the purchase was pre-tariff and before taxes were assessed on out of state purchases.
 
#24
I opened the pack and I can't find anything wrong. In fact, I have measured between pads in the packs and all were giving around the same volts (range of differences is within +/-0.05 volts, so it seemed pretty well).

When charging, I don't disconnect the charger immediately. I keep the bike in a storage room out of my flat, so I leave it charging for hours or even days, so in case a prolonged charge would help to balance cells, that would have already happened.

What seems to improve the behavior is to discharge the battery slowly (with a resistance -ie; a heater-). I make it go below the point where the led scale does not show any led lit. I stop around 32V cause I'm afraid of over-discharging, even when it is expected the BMS won't allow such over-discharge. A charge after that takes significantly longer, and doing that last weekend, I did a 45 Km route without any issue. Not sure if it has any explanation (like discharging overcharged -unbalanced- cells, and then the following charge will balance the pack) or it was just a lucky day.

My ideal situation is the battery may show signs of aging in the sense of shorter range, but at least does not power off. I understand a battery with 9000Km on it (after 3 years of usage) may have lost a significant capacity percentage, but what puzzles me is the battery stops completely at random.

According to bh bikes, Battery Life: maximum deterioration of 20% after 500 full- charge cycles> 30,000 km



When I had my battery pack opened I also cleaned my bms with isopropanol.



If I would get a new ebike today I would build it myself. Then you get control over the parts. And you can choose what battery you want, maybe get a extra battery. When bh battery cost over 1000 dollar you don’t get a extra. I don’t know if the rear motor works with other parts. I don’t think the controller or display works with other brands.
 
#25
If I would get a new ebike today I would build it myself. Then you get control over the parts. And you can choose what battery you want, maybe get a extra battery. When bh battery cost over 1000 dollar you don’t get a extra. I don’t know if the rear motor works with other parts. I don’t think the controller or display works with other brands.
I agree with you... although the route to build the bike does not guarantee an optimal bike for sports usage (my main usage), hence I prefer a different route.
I already have taken a step ahead and have bought a new bike: a Haibike fullseven from 2018 catalog. A double suspension bike At 2050 € I could not resist!!. It uses motor, battery and display from Yamaha, so at least the dependence is on a wider scale (ie; batteries from any brand using Yamaha system fits the bike) so you are not locked to a single vendor. Such a same the Yamaha 400Wh battery costs less than 500€ new (vs. around 800€ the BH one). Clearly BH is using the power of exclusivity on setting the prices.

A side benefit: the more widespread the electric system gets in the market (multiple brands use Yamaha) means the market of potential shops daring to repair any component is also much bigger than the limited ecosystem for a single brand.


... fair enough, this is not to blame BH, and in fact my challenge now is still to restore the EVO bike to usable condition to sell it or give it to my father (with full warranty it won't stop anywhere).
 
#26
Builds save no money. BUT, I have bikes that fit me perfectly. I’ve ridden so many bikes that just don’t fit me, or my lifestyle. We’re finding more and more older fellas coming to us to kit bikes they like, and have lived with long enough to know, their bike is the best choice. 1 of my flat foot frame builders has an eBike. I love Electra townies, but am not thrilled with a Bosch. Only because of lack of support and parts to repair. I like to ride, not do shop time. Now in fairness the likelyhood of a breakdown is rare... I hate life when I’m the 3% problem group having to wait. Depending on a shop mechanic makes me crazy. (50 year fan Idiots Guide to VW Repair)
Should ANY other manufacturer finally give a LBS, and build shops the ability to convert and sell... that will never happen. No standard frame mount. Sucks. Totally disappointing.

Making an alternative to gas spewing and buying eBikes has become somewhat elitist.

From my narrow perspective (a scant 5 years and a dozen motor types installed and ridden) a MAC, eZee, or the newest Bafang gear drives deserve far more attention in this market than the pricey mid drives. This is the high point for me reading about juiced bikes. MAC folks are top notch.

MAC motors will do the job for all but the MTB crowd. But even then, we have no local mountains and a MAC WILL ROCK THOSE TRAILS. Ok... mea culpa, this sounds more like a rant.

Bottom line, I like them all and EVERY quality motor has its place. The adventure is sorting out what your ideal build/motor is.

I’d like to see a CrMoly flat foot with a MAC and the newest Grin controller fitting in a Hailong pack.

at the end of the day, there are any number of bikes here I happily own and ride. Most, I think, are the kinder gentler fellas and gals that see eBikes as a positive change in sustainable transportation.

(Sorry, sent with our a proof read)
 
#27
Having purchased new batteries from BH for our Neo City and Cross we are still happy with the bikes. I have just replaced cassettes, chains, pads and blocks and fitted decent aluminium fender/ mudguards to the Cross. Rejuvenated.

The original 9ah City pack still charges and runs the bike. The problem was that when the charge level dropped to less than 80% the bike would cut out on hills. It would power down the display and stop. I recall it would power up again but you had to walk the rest of the hill. With two bikes and interchangeable batteries I could demonstrate the battery was the cause.

I wanted to see if there was an easy visible reason for the failure so I opened the pack gently using a hairdryer on the outside upper surface to soften the double side foam tape. This method is discussed elsewhere here or YouTube. I used plastic tyre levers to help separate the case. It wasn’t very difficult but you need to be patient while the adhesive softens and eventually gives up.

I found that white electrolyte (?) seems to have leaked from two cells. As I know little about lithium cells I will not guess what it is I am seeing or whether it the fault. Anyone who does know, please respond.

There is one incident probably 9 months ago that might be relevant. We were at the beach with the RV and I had prepared both bikes (batteries, displays, tyre pressures, rucksack, gloves, helmets, shoes all x2) when I got distracted. And forgot to lock the City battery. One mile later the pack fell off and hit the road at speed. The case is tough and there is barely a mark on where it hit the upper surface but it was a hard impact. The bike powered up fine when the pack was attached and continued to be fine for several months afterward. Cycling along largely flat canal paths and beach roads in France showed no issues. The problem first showed up climbing some big hills in Wiltshire. It was then fine on the level around Bristol and along the Avon river. Cornish hills around Heligan were the final straw. My wife had been struggling on despite the power cuts but my unwise “what happened to you, then?” comment as she pushed her bike up the hill towards me led to my understanding that something needed to be done.

I am going to assume this battery failure was caused by blunt trauma. I do not see myself attempting to repair it. It would be interesting to learn but I have other projects on. I have two, new batteries and a functional spare already. Batteries can deteriorate if neglected. We have four ebikes and five battery packs to maintain at 60% SOC so I have enough.

If anyone in the UK South is after a BH Neo City battery pack to re-cell let me know.
 

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ebikemom

Administrator
Staff member
#28
Drill few holes in the tube and use the mount ?
I'm not an expert on any sort of modification to a bicycle, but I do know that frame integrity is super important. I'd be interested in knowing how safe it is to drill holes in one's frame... Thoughts?
 

ebikemom

Administrator
Staff member
#29
Builds save no money. BUT, I have bikes that fit me perfectly.
As time goes by, I hope that there will be more and more shops that do builds and have the skills to maintain the builds that they do. It's a great idea to convert a bike-one-loves into an ebike. I also have wondered about my own ebike-I-love that also fits me so well ... what happens however many years and tens of thousands of miles down the line when it needs substantial refreshing? Surely that day will come? Will the brand offer that service, or will I need to find another solution, or will I need to decide that the bike is a goner and send it off to a landfill?

I think it would be really sad to see landfills fill up with discarded ebikes that folks aren't repairing or setting up with new systems to make them work again. Some of us who ebike also hope that our choices might be environmentally friendly ones. That's a mixed bag because we know that while the batteries we use don't pollute, and while the car-replacement-miles we ride benefit everyone, batteries have problems both in their manufacture and in their disposal, and the manufacturing of frames and components likely also pollute the communities where the factories are...

Anyway, just thinking out loud ...
 

Mr. Coffee

Well-Known Member
#30
I'm not an expert on any sort of modification to a bicycle, but I do know that frame integrity is super important. I'd be interested in knowing how safe it is to drill holes in one's frame... Thoughts?
Kind of depends on what the frame is made of... I wouldn't dare with a carbon fiber frame, but if you are talking about a beefy steel-framed bike and drillings holes in the top, bottom, or down tubes well away from joints you'd probably be fine.

The biggest issue is that you'd probably want to repaint the bike afterwards.
 

Thomas Jaszewski

Well-Known Member
#31
Kind of depends on what the frame is made of... I wouldn't dare with a carbon fiber frame, but if you are talking about a beefy steel-framed bike and drillings holes in the top, bottom, or down tubes well away from joints you'd probably be fine.

The biggest issue is that you'd probably want to repaint the bike afterwards.
Where on the frame can also be a mitigating factor. Frankly, I'm not a fan.
 

Thomas Jaszewski

Well-Known Member
#32
As time goes by, I hope that there will be more and more shops that do builds and have the skills to maintain the builds that they do. It's a great idea to convert a bike-one-loves into an ebike. I also have wondered about my own ebike-I-love that also fits me so well ... what happens however many years and tens of thousands of miles down the line when it needs substantial refreshing? Surely that day will come? Will the brand offer that service, or will I need to find another solution, or will I need to decide that the bike is a goner and send it off to a landfill?

I think it would be really sad to see landfills fill up with discarded ebikes that folks aren't repairing or setting up with new systems to make them work again. Some of us who ebike also hope that our choices might be environmentally friendly ones. That's a mixed bag because we know that while the batteries we use don't pollute, and while the car-replacement-miles we ride benefit everyone, batteries have problems both in their manufacture and in their disposal, and the manufacturing of frames and components likely also pollute the communities where the factories are...

Anyway, just thinking out loud ...
All the bearings and wear items are usually quite common. A well-made bike frame will last decades. Bearings and such are quite easy to replace. You're lucky to have a great fit. Many low-end eBikes are not well fit to riders. This is why I build. 5 years ago a bike I wanted did not exist.
 

ebikemom

Administrator
Staff member
#33
I did test riding. My bike is designed for comfort. I really like how my sitting and hand positions are so natural on this bike. :)
 

MarkF

Active Member
#34
Viper

You are over discharging your battery at 32 volts. You should never go below a resting voltage of 3.7 per cell. Doing so damages the battery. So multiply 3.7 times your batteries cell count and try not to go below that.
When your battery sits for more than a month, the chemistry in the cells go to sleep per say. Doing a discharge and charge cycle helps wake up the chemistry. So that is why you have seen an improvement when you did a cycle. But try not to discharge to low. Leaving the charging on after it has turned off or the light goes green, does nothing. The charging is done and turned off from doing any more charging. So unplug it and don't risk the charger doing something drastic.
As batteries age, they will always show a good voltage when checked but will dump as soon as a load is applied. This is how you know, your battery is basically done. You will get a little better voltage if the battery is warm and not cold so that will always help in getting better range before your ride. If you do a search on how long will my Li-ion battery last? They estimate 2 to 3 years or 300 to 500 cycles. All of this is dependent on how you treat your battery so I think 3 to 5 years is possible, but no one is really sure, because new cells come out every year. So there is no accurate data to prove anything except what 5 year old cells did.
 
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MarkF

Active Member
#36
I know you've seen the charts Thomas. 3.7 is 85% discharged. You can go lower under a load but Vipers discharge method is very low amp draw so there is very little spring back. He wrote he ran is pack down to 32V.
Unless he's running an 8s battery, that is way to low and why I addressed my comments to him.