Following on from my introduction to this forum I have questions

[lenny]

Maybe once upon a time, but coil has its place.
Smashpot is the latest thing

Smashpot V2 - Fork Coil Conversion System

Vorsprung Smashpot V2 - Fork Coil Conversion System

www.tftuned.com

cheap upgrade to ride pavements lol sensible advice for all

 

[Chainmale]

I sure do. Ride on the road too where I think it is safe. Must be the reason I've avoided accidents/close passes/etc

And I hope you also avoid close passes on pedestrians when riding on pavement

 

[saneagle]

At the risk of opening a can of worms, the biggest cause of battery degradation is charging to the end point. The battery depends on a very thin passivating layer to protect the electrodes. Each time you charge a battery to "full" you damage this passivating layer and then the electrodes underneath are degraded. This can lead to a loss of capacity

Complete and utter rubbish.
Bosch batteries charge to 42.0v
Yamaha batteries charge to 42.0v
Shimano batteries charge to 42.0v
Every Chinese 36v ebike battery charges to 42.0v

Are you going to write to them all and tell them they're wrong?

Anybody else. Do not believe that rubbish. If it were true, wouldn't even one of those do something different?

 

[Woosh]

42V is the limit for 36V Lithium batteries. You should consider that anything above 42V is at risk of overcharging your battery. The reason is you have a 10 high stack. If one block fails, the whole stack will overheat, the higher temperature will increase the flow of current and generate more heat, causing a thermal runaway leading to fire. You don't want to put all your blocks to their limit too often.
Batteries are chemical and also mechanical devices. During charging, Lithium ions (Li+) move from the cathode to the anode, causing the anode to swell. When it's full, the anode swells to double its size compared to when it's flat.
Like any flexible scaffolding structure, the more you push, the earlier it will rupture so it pays to leave some margin for extra safety.

Illustration of a cell during discharge. For charging, the Li+ ions move in the opposite direction, from the cathode to the anode. The anode is made with graphite which keeps Li+ between its layers like blankets.

 

[WheezyRider]

Complete and utter rubbish.
Bosch batteries charge to 42.0v
Yamaha batteries charge to 42.0v
Shimano batteries charge to 42.0v
Every Chinese 36v ebike battery charges to 42.0v

Are you going to write to them all and tell them they're wrong?

Anybody else. Do not believe that rubbish. If it were true, wouldn't even one of those do something different?

See what I mean Les? Opens a can of worms as soon as you mention charging and there are those that feel very passionately about it

4.2V/cell is a relatively arbitrary figure arrived at by battery manufacturers to indicate the end of cell charge point for Li ion cells. It is a compromise between best attainable capacity and cycle life. Charging to less than 4.2V/cell is widely acknowledged in the industry to increase battery life.

Basically, pushing a cell to 4.2 V is bad, but gives a reasonable life, say 500 or so cycles. Charging above 4.2V/cell is seriously bad and at 4.3V/cell cycle life may only be 100 or so cycles.

From the Battery University website:



So what can the average user do? Not much really unless they can do a fair bit of manual intervention. Hence most are tied in to using the industry standard 4.2V/cell. Battery life is reduced, meaning you have to buy another sooner than you should have to, but it's good for business.

The important thing I recommend is for people to check that their charger is not exceeding 4.2V per cell, so 42V for a 36V battery. This is especially the case if you are using a cheap charger bought online, or a charger designed for another battery. Some I have seen have outputted more than 43V. Also, some chargers are designed for a battery with a protection diode in the charge circuit, so they may give out around 42.5 V to 42.7V. If you plugged that into a battery with a BMS that did not have the protection diode it would be overcharging it and potentially doing damage.

 

[portals]

 

[Nealh]

By the time most users get to 500 cycles the battery will have aged naturally, so fuly charging isn't an issue if the battery is to be discharged promptly. I doubt many get near 250 charges unless a daily rider / heavy user.

 

[WheezyRider]

Not int he slightest, though some points seem about the mark

So lets split it down.

1. Actually a non eeb I'd say about £700. My first bike was the basic M200 Cannondale(in signature list) which cost aboout £500 in '94
Looking at how bike prices have gone over the last 30 or so years, 700 seems about right.
£2k for an Ebike looks about right. Mate's just bought a Carrera crossfuse which looks not bad for the money, if you can overlook the poor quality Suntour fork. Cost him £1800. Other than that its not bad at all.
I think most people here if you inc donor bikes, kit etc are going to be at least £1k, although there are a few members with bikes at the £4k price and above.
There are also members with more than one bike, 2 or ever 3 from the posts put up. Not sure where those members fit into your calculations, when clearly they have quite a few quid to throw at their chosen hobby/subject/transportation.

2. Against the law ?. Who said that ?? Not I, and please try to refrain from misquoting me or misinterpreting my point of view to suit.
I think there should be standards. Most here would agree, and while I dont want to bring any manufacturer who is on this forum into it, Im more than sure they have a good standard that they adhere to in choosing which bikes they bring to the market. Decent motors, decent batteries, safe chargers al adhering to British standards.
Its why we have standards you know. OK some people dont(yourself judging from your continual viewpoint, but am I my brothers keeper, and if they want to be lax in that department thats their look out.
People who join looking for advice on what to buy and usually showing links to some cheap import I point towards these members and their bikes because in my experience I find them to be good value for money, but not only that, but they look to provide their service at a high standard.

3. "All bikes should be mid drives" Where are you getting this nonsense from ?? Mid drive gives a good weight balance to a bike, especially when you've got weight with panniers on the back too
Weight distribution is an important factor.

4. "Anyone who has bought a £100 bike has made a foolish decision."
They've made a poor decision yes. Maybe they've listened to someone foolish they felt they could trust, who likes to project an air of expertise, but in reality they have sold that person a lemon.
Too little knowledge is a dangerous thing they say.

To finish. You say you've been at this for a long time but what exactly does that mean. Been riding your bicycle for a long time. Juswt riding a bike, even for decades dooesnt make you an expert.

I have lived bikes for the last 30+ years. Not just riding, I assemble my own. The only bike I've bought complete was the Cannondale, which was a birthday gift.
All the bikes in my signature I've built from the bare frame up. and all were built using the catalog spec of that year/model. I fix/service most parts, hubs,forks, brakes etc
Hydraulic brakes from the earliest Hope tech(non hydraulic cable), through the years I've used, and serviced every single Hope tech brake right up to the current Tech 4. , suspension forks from early RS indy, judy boxxer, early marzocchi from the XC through the bomber range, fox, modern RS or even Amp research and Lawwill leader.
If you have a prob with brakes or forks, I'll talk you through the service or if youre really stuck, I dont mind doing the work for you. I dont just invest in quality kit, i also invest in the tools needed.
I've worked for 2 bike charities as a bike mechanic, volunteering my time and experience to get bums on saddles
But I will never ever point or recommend a newbie something that isnt worth the money.

I take it words like Hope tech, Lawwill or Amp research are foreign words to you.

Heres a pic of my older Hope brake and hub kit I use to service and keep the retro stuff going. But its really a fraction of my bike collection of parts spanning Mountain bike history.
View attachment 52567

Ok, I think we are getting somewhere...

I was being very reductionist at the end of my last post to try and get a proper idea of where you stand so we can cut the waffle. Holiday ends today and I can't be on the forum all day every day

On 1), I've managed to haggle you down to about £700, so I suppose that's progress lol. That said, the bike I bought recently for around £850 after only 100 miles, one of the pedals had a bearing failure and fell apart. Then the bearing in the fancy dyno front wheel seized. It was fixed under warranty, but I ended up replacing the pedals for what I hope will last longer. I've never had that on any of my cheap bikes, so as i said, spending more is no guarantee of hassle free cycling.

For 2) as I said, being reductionist. You say you want standards, but unless they are backed up by law, what is the point? Unscrupulous manufacturers will just fake certificates etc. If there is no enforcement, who will care?

For 3) I just can't remember you ever saying anything positive about hub drives. Even when you defend yourself, you do so by pointing out why you think mid drives are better Go on, push yourself, say something nice about hubs

For 4) So to someone who has bought a bike for £100, run it for several years problem free that they have made a bad decision? OK...

Saying that you have "lived" bikes for however many years just makes it sound like you have travelled too far up your own back side to have a connection with the real world where ordinary people have to live to survive. It's great if you can give pointers to people who have plenty of money to buy something nice, but you are then talking down to the rest of the people who can't afford to spend a lot on bikes.

Maybe what would be useful is for you to use your experience to put together a guide for people on a tight budget, eg, what are the common failure points on cheap bikes and what to avoid/look for, rather than just writing anything off at the budget end of the market.

 

[WheezyRider]

By the time most users get to 500 cycles the battery will have aged naturally, so fuly charging isn't an issue if the battery is to be discharged promptly. I doubt many get near 250 charges unless a daily rider / heavy user.

Sad, but probably true. I am doing at least 2 cycles of charging a day and so for me it is important to try and prolong battery life. This year I have done about 400 cycles on my main pack and it still performs like new and I only ever charge it to 41V. Although what I do is not practical for most people. But I do worry about some chargers out there on the market that are giving out way too high a voltage, eg over 43V for a 36V pack.

 

[guerney]

View attachment 52557

should get a few cans of special brew in there says it can last 130 mins on fire nearly broke the car getting it home 100kg+

Leave the door ajar - a battery fire inside that will cause an almighty explosion.

 

[saneagle]

See what I mean Les? Opens a can of worms as soon as you mention charging and there are those that feel very passionately about it

4.2V/cell is a relatively arbitrary figure arrived at by battery manufacturers to indicate the end of cell charge point for Li ion cells. It is a compromise between best attainable capacity and cycle life. Charging to less than 4.2V/cell is widely acknowledged in the industry to increase battery life.

Basically, pushing a cell to 4.2 V is bad, but gives a reasonable life, say 500 or so cycles. Charging above 4.2V/cell is seriously bad and at 4.3V/cell cycle life may only be 100 or so cycles.

From the Battery University website:

View attachment 52575

So what can the average user do? Not much really unless they can do a fair bit of manual intervention. Hence most are tied in to using the industry standard 4.2V/cell. Battery life is reduced, meaning you have to buy another sooner than you should have to, but it's good for business.

The important thing I recommend is for people to check that their charger is not exceeding 4.2V per cell, so 42V for a 36V battery. This is especially the case if you are using a cheap charger bought online, or a charger designed for another battery. Some I have seen have outputted more than 43V. Also, some chargers are designed for a battery with a protection diode in the charge circuit, so they may give out around 42.5 V to 42.7V. If you plugged that into a battery with a BMS that did not have the protection diode it would be overcharging it and potentially doing damage.

It's not about passion. It's about telling guys to ruin their expensive batteries.

Battery University is a business selling chargers, not a University where people go and learn about batteries.

Does anybody think that none of the extensive teams of experts from Bosch, Shimano, Yamaha, Brose, Heinzmann and all the Chinese factories have seen that Battery University stuff that's been floating round for more than 10 years? Does anybody wonder why every single single charger supplied with every 36v ebike in the world charges to 42.0V?

Is it the Chinese, who have bribed them all because they have employment contacts that they can't cancel with all the slaves in Africa, who are digging up the lithium? Is it the deep state trying to thin out the population by making battery fires, or is it the World Economic Forum trying to make everybody go bust by making sure that they spend more money on batteries than necessary. Please somebody make sense of why they all want to charge to 42.0v, when WheezyRider knows that we'd all be better off if we didn't.

 

[Woosh]

every single single charger supplied with every 36v ebike in the world charges to 42.0V?

that's the output voltage of the SANS charger too, but what the voltage you see at the output is typically 41.3V-41.5V because of the drop through the charge and discharge junctions in the BMS.

 

[WheezyRider]

It's not about passion. It's about telling guys to ruin their expensive batteries.

Battery University is a business selling chargers, not a University where people go and learn about batteries.

Does anybody think that none of the extensive teams of experts from Bosch, Shimano, Yamaha, Brose, Heinzmann and all the Chinese factories have seen that Battery University stuff that's been floating round for more than 10 years? Does anybody wonder why every single single charger supplied with every 36v ebike in the world charges to 42.0V?

Is it the Chinese, who have bribed them all because they have employment contacts that they can't cancel with all the slaves in Africa, who are digging up the lithium? Is it the deep state trying to thin out the population by making battery fires, or is it the World Economic Forum trying to make everybody go bust by making sure that they spend more money on batteries than necessary. Please somebody make sense of why they all want to charge to 42.0v, when WheezyRider knows that we'd all be better off if we didn't.

Maybe you're right, after all, you are our resident expert on conspiracy theories LOL

So the industry "experts" on batteries can't be wrong, but all those guys in white coats who saved us from Covid and all sorts of other illnesses through developing vaccines are a bunch of con men trying to take over the world? Funny your cognitive dissonance there...

Don't take my word for it. Just the hundreds of PhDs on Li ion battery studies. Who knows, maybe these guys are cowboys?



From:

Cycle Satiator Lithium Battery Charge Simulator

The Satiator Charge Simulator is a web application for creating custom charge profiles for your lithium battery pack. It allows you to view a simulated charging graph to see the charging time in difference scenarios, produce partial charge profiles to maximize battery cycle life, and download...

ebikes.ca

Plus NASA have done loads of studies and have actually concluded 3.9V/cell is best

But whatever. Charge to 4.2V per cell if that makes you happy. 4.2V/cell as I said, is a compromise between capacity and cycle life. It is what the industry has decided to use. Doesn't mean it is the best value for cell longevity.

As I keep repeating, my message is for most people, just keep charging to 4.2V/cell, it's only those who have enough expertise who can experiment with lower voltages. But, if you can, mainly for your own safety, you should check that your charger is not giving out more than 4.2V/cell if you have bought a replacement charger say from eBay etc.

 

[Nealh]

What is best voltage wise is one thing but for practicality it some what reduces one range so would force a larger heavier battery to be carried.
Generally for the average Tom, Dick or Harry charging to 4.2v will suffice .

 

[StuartsProjects]

Plus NASA have done loads of studies and have actually concluded 3.9V/cell is best

On the satellite I built, the Lithium Ion battery was indeed charged to 3.9V.

The battery survived in excess of 8,000 charge cycles, it might have survived longer than that but the solar panels failed after 20 months.

The battery was also cycling from -30C to +30C every circa 100 minute orbit.

Lithium Ion batteries do seem to last if you look after them.

 

[I893469365902345609348566]

I have a 36 volt battery which went like that. I had to open the case to measure the voltage of all the groups and found one group at 3.3 volts while all the others were at 4.2volts. I charged it separately with a 4.2v charger and monitor it through some extra contacts on the outside of the case (insulated for safety). I now keep it in balance and the two year old battery is performing great as long as I do this. When it was badly out of balance, the battery would shut off at about 2 miles. Now I can get well over thirty odd with the same effort on the pedals.

Could you say how you charged just one group? What did you use to charge it with?

 

[WheezyRider]

Could you say how you charged just one group? What did you use to charge it with?

You need to put a meter across the different cell banks and identify which one is low. Then, use something like a Poundland USB bank, take the circuit out of it and desolder the battery inside and instead connect that to your bank that is out of balance. Allow it to charge the bank to the same voltage as the surrounding banks. Keep an eye on it.

You do need to be careful and if you are at all not sure, post pictures on here and ask for help.

 

[lenny]

https://www.lithiumbatterypcb.com/product-instructionev-battery-pcb-boardev-battery-pcb-board/ev-battery-pcb-board/smart-bms-of-power-battery/