Battery charge cycles

[Nealh]

Andy doesn't get it sometimes, all my generic China chargers don't supply any charge once the battery BMS ceases the charging or the charger set voltage is reached. They go from being slightly warm to cold.
Even adjusting the pot voltage to 41v they stop charging.

Andy along with a couple of other newer users are the forums scare mongers.

 

[MontyPAS]

Andy along with a couple of other newer users are the forums scare mongers.

By agreeing to the post my intention was not to "Scaremonger" users of the forum.
It is just the method I have got into when charging unattended batteries, be they Pedelec batteries or Makita 18v Li-Ion units. As a bonus I personally, have found 18v tool batteries have had an extended life using this procedure, I have gone through enough Makita units in my time.

As a side note, personally I do not like leaving unattended charging batteries connected to the mains.
A mechanical timer gives for both the battery and charger electrical isolation from mains voltage once the predetermined time is up.

Not gospel just my views.

 

[Swizz]

My car has a charge setting where it will shut off at 80% to protect the battery if it is not going to be used straightaway. Could a charger not be modified to switch off at a lower state of charge?

 

[Benjahmin]

Car systems are way more sophisticated than bike systems. Bike bms has top down bleed resistors to balance cell strings. Therefore, if you only charge a bike battery to 80% it cannot balance.
Also if battery voltage achieves the same level as the charger output voltage the no current flow can occur.
So, don't fret. Use it, charge it, enjoy it. Just don't charge and leave for a long period before use. Don't leave for a long period at too low a charge.
Simples.

 

[Edward Elizabeth]

My car has a charge setting where it will shut off at 80% to protect the battery if it is not going to be used straightaway. Could a charger not be modified to switch off at a lower state of charge?

A bit like the way the petrol pumps cut out when the tank of my 5 litre Range Rover is brimmed

 

[Swizz]

A bit like the way the petrol pumps cut out when the tank of my 5 litre Range Rover is brimmed

If I had to fuel a 5l Range Rover I would be a sobbing mess!

 

[Swizz]

Car systems are way more sophisticated than bike systems. Bike bms has top down bleed resistors to balance cell strings. Therefore, if you only charge a bike battery to 80% it cannot balance.
Also if battery voltage achieves the same level as the charger output voltage the no current flow can occur.
So, don't fret. Use it, charge it, enjoy it. Just don't charge and leave for a long period before use. Don't leave for a long period at too low a charge.
Simples.

Makes sense, thank you

 

[Edward Elizabeth]

If I had to fuel a 5l Range Rover I would be a sobbing mess!

Much of my mileage is work related and gets written off against tax. I'd love an electric car, but when suddenly work requires me to be in Turin in 18 hours time and there is no flight available within that window then the only option is to get in the car. An electric car wouldn't get me to Dover, never mind the 850 miles to Turin. (I did it in 16.5 hours, if anyone is interested, and came back via the south of France as I had a client there I needed to see).

But I'm hoping to finish work soon and sell the firm, so and electric car will be eminently suitable for us. I'm liking the look of the new Polestar 2.

Ps, apologies for the off topic excursion.

 

[Swizz]

Much of my mileage is work related and gets written off against tax. I'd love an electric car, but when suddenly work requires me to be in Turin in 18 hours time and there is no flight available within that window then the only option is to get in the car. An electric car wouldn't get me to Dover, never mind the 850 miles to Turin. (I did it in 16.5 hours, if anyone is interested, and came back via the south of France as I had a client there I needed to see).

But I'm hoping to finish work soon and sell the firm, so and electric car will be eminently suitable for us. I'm liking the look of the new Polestar 2.

Ps, apologies for the off topic excursion.

16.5hrs...wow that is some going!

 

[Sturmey]

.....Could a charger not be modified to switch off at a lower state of charge?

There is a DIY modification that works with most chargers (e.g 2 wire). It requires a switch and some (e.g 5 amp) silicon diodes and some technical skill. The diodes are placed in series on one power leg by cutting the charger to battery cord and this reduces the voltage. The switch is used to switch out the diodes to give full normal charge.

 

[Swizz]

There is a DIY modification that works with most chargers (e.g 2 wire). It requires a switch and some (e.g 5 amp) silicon diodes and some technical skill. The diodes are placed in series on one power leg by cutting the charger to battery cord and this reduces the voltage. The switch is used to switch out the diodes to give full normal charge.

Interesting. Think my charger is 3 wire tho. Do you have a link?

 

[Nealh]

My Sans and another China charger I have have/has an adjustable voltage pot, I have modified all my chargers for better air flow so they don't get remotely hot now and and extra casing hole so I can simply adjust/check the output with my meter.
As I have 4 or 5 chargers I mark two with Tippex, one is set to 41v, one at 38v & all the others are at 42v.

 

[nigelbb]

If I had to fuel a 5l Range Rover I would be a sobbing mess!

My RANGE ROVER V8 4.6L does a very creditable 18+mpg

 

[georgehenry]

If you do not have the technical skills and/or are lazy like me you can buy a timer plug to either cut the power to the charger when you know it will have finished charging the battery or to do a partial charge, for example if your battery is below the level you are comfortable storing it but do not want it fully charged.

https://www.amazon.co.uk/gp/product/B005C9S0I8/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

I have one in the garage and one in the house.

My rear hub bikes have silver fish batteries behind the seat post and you have to remove the seat post to remove the battery. I cannot be bothered and they stay on the bike in the garage.

When I return from shopping etc I park the bike in the garage next to the plug and connect them to the charger via the timer plug. It is simple and quick and I decide length of charge I want the battery to have by clicking a start stop button on the plug. It takes a few seconds.

No where near as good as using a multi meter and making custom adjustments but never the less very simple and effective, making my cheap silver fish batteries last a long time.

The battery on my Haibike has a built in carry handle and fixes on the down tube and is very easy to remove and carry into the house after my ride back home from work, and as a consequence I always do that.

The trend now seems to be to hide/build in the battery to be contained within the down tube rather than attaching to it and they look a bit more difficult to remove, although I have never owned one so do not know if they are.

Personally I do not mind people seeing my battery and knowing I am riding an ebike and love how easy it is to remove and attach the battery on my entry level Haibike, which I do both at work when I arrive and leave and at home to take it in the house to charge or store and then to attach it when I go to work.

My daughter tells me that laziness is a survival trait that humans evolved to have. I must be highly evolved!

 

[sjpt]

It is bad to charge at low temperatures, below or just above freezing.
Beware if charging on the bike in a shed or unheated garage in the winter.

Especially relevant with bikes with hard to remove battery.

 

[MontyPAS]

https://www.amazon.co.uk/gp/product/B005C9S0I8/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

I have one in the garage and one in the house.

That's a handy looking timer with the set presets, ideal for isolating battery from charger. Will try one!

 

[D C]

That's a handy looking timer with the set presets, ideal for isolating battery from charger. Will try one!

You might as well buy two from that link as less than £2 more for two! I use these and they're excellent.

 

[MontyPAS]

You might as well buy two from that link as less than £2 more for two! I use these and they're excellent.

Good point, just ordered two

 

[georgehenry]

First ride to work after a 21 day lay off for my Haibike bike and battery during my summer holiday break, 12 miles cross country to work and then 10 miles back home in the small hours on the road. The joys of shift work.

So I charged my almost 5 and a half year old 400Wh Yamaha battery to full at home within a couple of hours of setting off to work at just after 13:30.


These sheep appeared to have been freshly sheered. I thought you sheered sheep after the winter before the summer. What do I know, nothing.


I noted when I arrived at work at the end of my 12 mile almost completely off road ride that I had used a miserly 28% of my battery. On my ride to work I only use the lowest assist and some sections like the field in the picture above, no assist.

The Yamaha motor is very nice to ride without motor assistance and seems to add absolutely no drag at all. I was also carrying more weight than normal in my panniers. At work I removed my battery and plugged it in to charge.

Much later, there was trouble at the mill, though I get paid overtime at time and a half if required, though I would prefer to be in bed, I rode 10 miles home on the road at about 01:00AM in the morning.

At that time of night, after a long shift I want to get home quickly and use the middle higher assist level of the three I have to climb hills quicker and ride the 10 miles I have to travel in around thirty minutes to average 20mph.

When I got home I had used 34% of my batteries capacity, and removed it and took it into the house to store at 66% charged until I next need to use it.

That could have been today but the reason I have the time to write this as although I am working today I am on call at home with my fingers crossed that I do not get called.

The latest I can be called to do some work is 21:40, but I reasonably sure I will not be and it is nice to sit at home being paid.

I keep a note of my bike's mileage that with last night's ride has crept up to 12,474 miles.

 

[BazP]

My off road rides average 35 to 40 miles and I always fully charge the battery after each ride as I don’t want to be charging at 7.00 am before a ride. Also, I may not go on a ride for several days due to bad weather, leaving the battery fully charged. This has been going on for three years and the battery appears as new.
Posters keep talking about reducing life expectancy of the battery So how do I determine the life expectancy of my battery? Is it five years or ten years or one year? If it packs up tomorrow have I had good use out of it? I think that I would just charge it and ride it and assume that the manufacturer know what they are doing. My partner’s battery is just the same so I’m not just lucky.