Battery Care Tips?

Cancunia

Pedelecer
Aug 6, 2021
50
8
I got a new 36V 15AH Silver Fish battery from Yose power yesterday. I charged my battery before use, it took a few hours for the charger light to go green, no surprise I suppose. After charging I tested the battery on the bike for about 20 mins & it worked fine, then recharged it when I got home which took about an hour, then disconnected the charger.
This morning, I plugged the charger in & was surprised to see that the charger light went red. I thought it would hold it's charge overnight?
Apologies if there's a thread on the subject of charging & maintaining batteries, I'm still a bit new to all of this. If there's a useful thread or 2 on the subject, please paste links?
Thanks
 

Tony1951

Pedelecer
Mar 27, 2016
193
90
70
I would have thought it would go red for a short time and then go green.

My charger shuts off at 42 volts and the battery soon settles back to about 41.8 or 41.6. I think if I reconnected the charger at that level it would charge for a few minutes and then cut off.
 
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RoadieRoger

Esteemed Pedelecer
Nov 8, 2010
686
159
The Charger that came with my Yose 15h Battery puts out 41.95 Volts and usually after a full charge to green , the reading on the LCD 3 handlebar Meter of my Lanarkshire E Bikes Fat Tyre is 41.7 Volts . Yesterday I did a very short 4.3 mile trip involving half flat and half fairly steep climbs on narrow lanes and lost about 1 Volt . For short trips I wouldn`t bother charging but my next ride is likely to be about 35 miles , so it`s being topped up as I write this .
I find a Multimeter handy and periodically check the Charger Output as well as removing the Battery to check the Voltage v Time to get to a Full Charge when the red indicator turns to green on the Charger . Normally the Battery is charged in-situ . On a longer trip I expect to get over 40 miles out of my Yose which needs about three and a half hours on my route . Any longer my Wife who is totally dependent on me goes hungry or gets angry and sometime both !
 
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vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,922
Basildon
That's perfectly normal because there are bleed resistors that drain down the cells to do the balancing. Imagine a bucket of water with a small hole drilled in it about an inch from the top. You can fill it to the top, but when you go back later, it'll be level with the hole.
 

Andy-Mat

Esteemed Pedelecer
Oct 26, 2018
1,813
437
74
I got a new 36V 15AH Silver Fish battery from Yose power yesterday. I charged my battery before use, it took a few hours for the charger light to go green, no surprise I suppose. After charging I tested the battery on the bike for about 20 mins & it worked fine, then recharged it when I got home which took about an hour, then disconnected the charger.
This morning, I plugged the charger in & was surprised to see that the charger light went red. I thought it would hold it's charge overnight?
Apologies if there's a thread on the subject of charging & maintaining batteries, I'm still a bit new to all of this. If there's a useful thread or 2 on the subject, please paste links?
Thanks
Try to only recharge when you need extra range, as each charge, long or short, takes away a charge cycle from the number that your particular battery has "in it!".
Sadly, the exact number of charges your battery will handle, lies in the lap of the Gods!
But reckon with good care, it will probably (see I am being careful with the numbers!) between 2000 and 3000, say 2500 on average!
The best way to treat a battery, is to run it down to the point where the controller shuts down assistance due to low voltage, which is for a nominal 36 volt battery, somewhere around 29 to 30 volts usually.
This is what I did with my first e-bike, even though I had only the one battery.
With my second e-bike I bought two batteries, and when I guess that the one installed may fail on my ride, I take the second battery with me, but I may just ride the bike without assist back home, depending on where I am.
My bike allows quite rapid and very easy battery swaps, not all do!!
regards
Andy
PS. I forgot to mention, that up to now, with two bikes, 11 years e-bike riding, and in all 3 batteries (all cells from Panasonic, though that was more by accident than design!) I have never had a battery fail completely and need to be replaced. My last e-bike I gave away in full running order, 6 years with me and one with the previous owner, with the original battery still in fine form, so I must be doing something right......as did the first owner of the first e-bike of course!
Not everyone here agrees with this philosophy though!!!
 

RoadieRoger

Esteemed Pedelecer
Nov 8, 2010
686
159
The Charger that came with my Yose 15h Battery puts out 41.95 Volts and usually after a full charge to green , the reading on the LCD 3 handlebar Meter of my Lanarkshire E Bikes Fat Tyre is 41.7 Volts . Yesterday I did a very short 4.3 mile trip involving half flat and half fairly steep climbs on narrow lanes and lost about 1 Volt . For short trips I wouldn`t bother charging but my next ride is likely to be about 35 miles , so it`s being topped up as I write this .
I find a Multimeter handy and periodically check the Charger Output as well as removing the Battery to check the Voltage v Time to get to a Full Charge when the red indicator turns to green on the Charger . Normally the Battery is charged in-situ . On a longer trip I expect to get over 40 miles out of my Yose which needs about three and a half hours on my route . Any longer my Wife who is totally dependent on me goes hungry or gets angry and sometime both !
 

RoadieRoger

Esteemed Pedelecer
Nov 8, 2010
686
159
My ride this afternoon exceeded 35 and reached 37 .1 miles over 3hrs 15 minutes . A mix of A roads and lanes with some long gradients . I monitored time and distance using a Holux GPS on my left wrist and the Voltage readout from the LCD . At the start it read 41.8V and after 37.1 miles the reading was 35.5V . Half of my power indicators remained at the end of the ride .
I am confident Cancunia that your new 15Ah Yose will easily give you 40 miles .
 

Tony1951

Pedelecer
Mar 27, 2016
193
90
70
It's a bit of a dark art estimating how far you can go. It depends on a longish list of variables: the all up weight of the bike and rider; how much effort the rider puts in, vs how much the motor is asked to deliver; the nature of the road surface and terrain; headwinds; average speed; tyre type; tyre pressure; bike condition; age of battery; ambient temperature. All of these will alter the range, some more than others. Hills are obviously the big power sucker.

You just have to try it and see, and whatever you find, will only fit that route if you live in a hilly place like I do. Some routes of mine require 3000 feet of climbing, others, much less. My 13ahr 36 volt battery managed about 40 miles mostly set on PAS level 2 of 5, on a route involving 3000 feet of climb on my 250 watt Baffang mid drive conversion. I think the cells are Samsung 10s 5p, so there are fifty at something like a notional 2800 Mahr capacity. I sometimes used throttle on the hills and PAS 5 which was drawing about 600 watts, but I did that sparingly.

In the early days when I first got it, I managed sixty miles,but I was pretty mean on using the power and rode quite a bit in PAS1.
 

Cancunia

Pedelecer
Aug 6, 2021
50
8
Thanks for the feedback so far. I did 15 miles yesterday and the battery indicator went down from 4 lights to 2 then back up to 3. I did a lot of miles on full speed via the twist grip (14.8 according to my Halfords trip meter) with little or no pedalling. There were a few fairly steep hills that I pedalled with the twist grip near to full too. I was tempted to recharge the battery after every ride, but it makes sense as mentioned above to only recharge when the battery is approaching empty. I've bought a larger chainring so that pedalling at 12-15 mph is not so frantic.
I think I'll buy a voltmeter, mount on the handlebars and connect directly to the battery output, I read various reports about the accuracy & daylight visibility of such devices but maybe worth a shot.
 
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Andy-Mat

Esteemed Pedelecer
Oct 26, 2018
1,813
437
74
Thanks for the feedback so far. I did 15 miles yesterday and the battery indicator went down from 4 lights to 2 then back up to 3. I did a lot of miles on full speed via the twist grip (14.8 according to my Halfords trip meter) with little or no pedalling. There were a few fairly steep hills that I pedalled with the twist grip near to full too. I was tempted to recharge the battery after every ride, but it makes sense as mentioned above to only recharge when the battery is approaching empty. I've bought a larger chainring so that pedalling at 12-15 mph is not so frantic.
I think I'll buy a voltmeter, mount on the handlebars and connect directly to the battery output, I read various reports about the accuracy & daylight visibility of such devices but maybe worth a shot.
What one really needs, is what is called a SOC Meter, or State Of Charge meter.
Cheap ones are mostly useless, as they vary wildly with the changing load.
Someone here (last year?) mentioned knowing one that was correctly damped and gave a more accurate reading. With a bit of luck he will help you further....
SOC meters take into account both current drawn and voltage at one and the same time (if I remember correctly)...The one built into my own bike display is average, and fluctuates quite heavily, you need to ignore the road and watch it for 10 seconds to read, which I do not recommend....
A SOC meter, is really a fancy type of volt/current meter.
Do not forget that a normal voltmeter will also be difficult to read while riding, due to those fluctuations (and fluctubritish too!) I mentioned.
Best wishes
Andy
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,922
Basildon
Thanks for the feedback so far. I did 15 miles yesterday and the battery indicator went down from 4 lights to 2 then back up to 3. I did a lot of miles on full speed via the twist grip (14.8 according to my Halfords trip meter) with little or no pedalling. There were a few fairly steep hills that I pedalled with the twist grip near to full too. I was tempted to recharge the battery after every ride, but it makes sense as mentioned above to only recharge when the battery is approaching empty. I've bought a larger chainring so that pedalling at 12-15 mph is not so frantic.
I think I'll buy a voltmeter, mount on the handlebars and connect directly to the battery output, I read various reports about the accuracy & daylight visibility of such devices but maybe worth a shot.
Don't run the battery to its cut-off point if you can avoid it. Always charge your bike to full before you ride it unless you're only going for a short ride. Advice above is from somebody that prefers to install his brakes backwards, so be careful.
 
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slowcoach

Pedelecer
Dec 11, 2020
102
70
If my bike battery can last for 2000 charges, that means I could charge it every day for about 5 1/2 years.

I wonder if I will still be around in 5 1/5 years?
 

Andy-Mat

Esteemed Pedelecer
Oct 26, 2018
1,813
437
74
Don't run the battery to its cut-off point if you can avoid it. Always charge your bike to full before you ride it unless you're only going for a short ride. Advice above is from somebody that prefers to install his brakes backwards, so be careful.
If you understood metallurgy correctly and better, you would understand why......but if you don't you will continue to make the same mistakes......
Furthermore, the motor controllers are set up to understand far better than you when it is safe to stop supplying power to the motor, and the controller designers/programmers of them REALLY know what they are talking about and how to do it, trust their advanced knowledge!
Have a great day, I am, you gave me a great laugh, again!
Many thanks
Andy
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
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If you understood metallurgy correctly and better, you would understand why......
Yes, I know quite a lot about metallurgy. I'm a graduate chartered mechanical engineer. That was my first career. Where did you get your lack of knowledge from? We know - you read something on the internet.
 
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Nealh

Esteemed Pedelecer
Aug 7, 2014
14,195
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West Sx RH
Thanks for the feedback so far. I did 15 miles yesterday and the battery indicator went down from 4 lights to 2 then back up to 3. I did a lot of miles on full speed via the twist grip (14.8 according to my Halfords trip meter) with little or no pedalling. There were a few fairly steep hills that I pedalled with the twist grip near to full too. I was tempted to recharge the battery after every ride, but it makes sense as mentioned above to only recharge when the battery is approaching empty. I've bought a larger chainring so that pedalling at 12-15 mph is not so frantic.
I think I'll buy a voltmeter, mount on the handlebars and connect directly to the battery output, I read various reports about the accuracy & daylight visibility of such devices but maybe worth a shot.
The bounce back from 2 lights to three is the battery sag , once the current demand is reduced the voltage rebounds giving a near true indication
On my bikes I use a KT display with a pretty accurate voltage readout and always know the true battery SOC/voltage, otherwise one can wire up simple 2 wire voltage LED.
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
14,195
5,498
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West Sx RH
As vfr has said always charge full before a ride unless you are just going on errands or very short trips locally of up to 5 miles.
 

Cancunia

Pedelecer
Aug 6, 2021
50
8
I've done a fair amount of reading over the past day or so on the subject of Li Ion battery care. It seems that to achieve the highest amount of charge / discharge cycles while at the same time retaining the highest capacity, the battery should not be charged to above about 80-90% voltage/ capacity, and not fully discharged. Obviously, charging to below max capacity also means less range. I would hope that the BMS would cutoff at a safe discharge level so as not to seriously affect battery life.
Voltage measurement for checking Li Ion battery capacity is not a very precise art beyond full & empty as the batteries have a fairly flat discharge rate vs voltage curve. The only way to be more accurate for a reasonable price when measuring State of Charge is using a coulomb counter / coulometer , these are available for about £25 from China via eBay / Bangood.

I'm happy to be corrected on any of the above, if I've misunderstood.

Some references for further reading:

Coulometers
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,922
Basildon
I've done a fair amount of reading over the past day or so on the subject of Li Ion battery care. It seems that to achieve the highest amount of charge / discharge cycles while at the same time retaining the highest capacity, the battery should not be charged to above about 80-90% voltage/ capacity, and not fully discharged. Obviously, charging to below max capacity also means less range. I would hope that the BMS would cutoff at a safe discharge level so as not to seriously affect battery life.
Voltage measurement for checking Li Ion battery capacity is not a very precise art beyond full & empty as the batteries have a fairly flat discharge rate vs voltage curve. The only way to be more accurate for a reasonable price when measuring State of Charge is using a coulomb counter / coulometer , these are available for about £25 from China via eBay / Bangood.

I'm happy to be corrected on any of the above, if I've misunderstood.

Some references for further reading:

Coulometers
You've been reading the wrong stuff. That's how to manage lithium cells, not how to look after an ebike battery. Your battery is managed by a BMS. You can hope what you like. It won't change anything. We gave you good advice. Do something different if you want, then come back and tell us how we'll it worked (or didn't). While you're at it, you might as well put your brake discs on backwards if you like to take irrelevant advice from the Internet rather than from people that know what they're talking about.

You can get a wattmeter from Ebay for about £8 that will give a fairly accurate measurement of battery capacity, range and state of charge. It'll teach you a lot about how your bike works, some of which is counter-intuitive.
 
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