Charger stolen
- Thread starter Steve 55
- Start date
They generally cost under 40 UK Pounds on UK ebay.
You must make sure that the connector and polarity are correct for your bike.
If the charger you want is wrong, or is found to be wrong before using, its easy to solder up a small adapter cable to convert to the correct type and polarity, without cutting off the original connector from the charger and ruining the guarantee!
There are 2 and pin chargers.....
Add a car fuse holder in the adapter cable to make life a bit safer too, available at Halfords!!
A multi-meter can be a great help, as well as a mate who understands batteries and soldering if you don't!
UK ebay:-
https://www.ebay.co.uk/itm/24V-Lithium-Battery-Charger-Adapter-29-4V-2A-For-Electric-Bicycle-E-Bike-Scooter/292794844254?epid=23025307452&hash=item442beec45e:g:HUUAAOSwsPNb4-LE:rk:1:pf:0
This one you can specify different connectors:-
https://www.ebay.co.uk/itm/Ebike-24V-36V-48V-2A-Charger-fr-Electric-Bike-LiFePO4-Battery-Bicycle-E-Bike/183035852349?hash=item2a9dc9763d:m:mK2c0siCnBg_MffD5d-OS5Q:rk:28:pf:0
German ebay "WWW.ebay.de" seems to have far more 24 volt ones than UK ebay, and as most of them come from China anyway, it hardly makes and difference. The sellers understand English better than German anyway!
Here are some examples, but do not pick one with more than 4 amps for safety reasons, 2 amps is the safest:-
https://www.ebay.de/itm/E-Scooter-DC24V-2A-Power-Charger-XLR3-Lifepo4-Li-ion-Lithium-Battery-E-Bike-220V/282871234392?hash=item41dc707f58:g:~NcAAOSwJuZbvYHf:rk:4:pf:0
https://www.ebay.de/itm/29-4V-2A-Charger-rechargeable-Li-ion-battery-e-bike-24V-25-2V-25-9V-29-4V-7S-XLR/303067738184?hash=item46903eb048:m:mMpC97WEwxW6Dj9Sjsuy8ug:rk:2:pf:0
Don't forget to request a UK plug!!
regards
Andy
This is the one.
https://www.ebay.co.uk/itm/24-29-4V-2A-Lead-Acid-Battery-Smart-Charger-3-Step-for-Electric-bicycle/233032514989?hash=item3641d1fdad:g:eJAAAOSw1ExcBVh3&redirect=mobile
From UK if you need one in a hurry.
https://www.ebay.co.uk/itm/Electric-Bike-24V-1-5A-Lithium-Li-ion-Battery-Charger-Lipo-DC-29-4V-Scooter/153282315826?epid=25026529499&hash=item23b0568632:g:9j8AAOSwXi9b~5un&redirect=mobile
https://www.ebay.co.uk/itm/24-29-4V-2A-Lead-Acid-Battery-Smart-Charger-3-Step-for-Electric-bicycle/233032514989?hash=item3641d1fdad:g:eJAAAOSw1ExcBVh3&redirect=mobile
From UK if you need one in a hurry.
https://www.ebay.co.uk/itm/Electric-Bike-24V-1-5A-Lithium-Li-ion-Battery-Charger-Lipo-DC-29-4V-Scooter/153282315826?epid=25026529499&hash=item23b0568632:g:9j8AAOSwXi9b~5un&redirect=mobile
Plenty on Ebay ranging from £10 upwards , mainly from China . I didn`t get success with the Jing Cheng Model from China which is larger and has cooling slots and can be taken apart . A Lancashire Company Batt_shop have a PowerSmart 24V 1.5A Output with a 1 year warranty for £24.49 . This is the compact type which cannot be serviced , I had one of a similar design which lasted 3 years and on splitting to investigate the failure , a component had overheated . The ones supplied from China are more of a risk, as if faulty, will cost more to send back than their worth . Check that the plug that goes into your battery is the correct type , as there are at least 3 types and of course a UK 3 Pin Plug is more desireable .
To recap, a £12 one delivered from China is an acceptable risk , but not a £40 one . In the latter price range a UK Supplied one would be safer . Also take care as the Chargers vary for Lithium and Lead Acid , as they look similar .
To recap, a £12 one delivered from China is an acceptable risk , but not a £40 one . In the latter price range a UK Supplied one would be safer . Also take care as the Chargers vary for Lithium and Lead Acid , as they look similar .
A good post, one that reminded me about a point with my pwn charger, it has a tiny fan in it and blows slightly warm air out, but does not get hot itself.
It came with my bike, but is 36 volt....So I feel a fan is useful, provided you don't charge outside when it rains.....
regards
Andy
Chargers are a science in themselves Andy . My tale is an interesting one . My Batribike Quartz came with a Charger which listed a 31. 5 Volts Output . After 5 years I had the battery re-celled by Jimmy with 18650 Cells which pushed up the Quartz`s Battery from 8Ah to 11Ah and a new charger was posted back to me with instructions not to use the original . After 3 years this Charger supplied by Jimmy failed , so with no Charger what was I to do ? Well I dis-obeyed instructions and used the original . The result , a faulty battery . Well I ordered a new Charger on Ebay from China and this together with the Quartz Battery was sent to Jimmy to fix . Jimmy said it put out a little more volts than 29.4 which is the target but it was ok to use . I then sent for another one from China which was the larger one with the cooling louvres and by Jing Cheng . Using my Multimeter I was unable to get a steady reading of Volts output despite soldering a new lead and a new aviation type connector to it . Then after taking this one apart I decided to do the same to the original Charger supplied with the Quartz . Luckily I spotted an adjustable screw which varied the voltage and reduced this to 29.4 from the original 31.5 V as supplied .
This is the charger I now use and the Chinese Ebay one is a spare .
This is the charger I now use and the Chinese Ebay one is a spare .
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On re-reading my Saga above I should have emphasised the importance of measuring the Voltage Output of any Charger that is purchased, before connecting to the Ebike Battery . This means using a Multimeter . An instrument in the £10 to £20 price range would be best . I bought a spare costing £5 which is extremely good but for the positive probe falling apart internally .
I think that your experiences and knowledge gained will be a good lesson for many drivers of e-bikes and the like.
Over charging will always be the death of all batteries, not just Li-ions!
As you clearly point out, a cheap multi meter and a small amount of knowledge can save a lot of money in the long run! Not forgetting that overcharging Li-ion batteries can even cause bad fires under certain circumstances.....
It has surprised me personally that there are people here who sadly do not possess a meter, or do not know how to use it! It is as you point out with your experiences, far cheaper than a new battery.
My last e-bike was secondhand when I bought it, I used it several times daily for 6 years and the battery was still giving full distance (50 Km with assist) when I gave it away! A friends mother who had the same bike, had to buy a new battery after 12 months! The reason being that if she was not riding it, she had it on charge!
Many here still do not understand that even when a good charger goes green, it is not "OFF"! As there is still a small charge still happening that is very bad for the battery as in the long term, that is anything over a few hours after "full"!
I sincerely believe that many modern chargers are getting better, but up to now, I have not found one that switches off completely! Though I have only looked at about 6, maybe not the whole story!
For that reason, I use a simple electro-mechanical timer, that I have rewired so that the tiny synchronous motor is fed from the mains AFTER the internal switch.
I know roughly how long a charge takes, so I set the timer for a bit longer, and it removes all power completely to the charger and switches itself off completely and cannot switch on again!!
If the timer is needed for the original function as well, a simple changeover switch can be used, selecting either completely off at timer function, or the original sequence of timing...... It only takes about 10 minutes, a switch and a soldering iron!!
I have used such timers for at least 30 years (probably longer!) or so, when charging any type of battery.
I hope your new battery lasts and lasts!!
regards
Andy
Andy-Mat,
That is good advice to avoid overcharging batteries.
I found this article which claims that “keeping energy levels between 20% and 80% can double your battery lifespan or better”.
https://electricbikereview.com/forum/threads/the-poor-mans-battery-saver-satiator-a-10-outlet-timer.22564/
Like you, the writer used a cheap 24 hour mechanical timer similar to this one from Amazon:
https://www.amazon.co.uk/Mechanical-Interval-Socket-Security-Programmable/dp/B01M8JWTAK
Can you clarify something for me please?
Is the timer to be used just as intended (set it for the charger to be on for a 4 hour charge, say) or is it necessary to rewire it internally
to guarantee switching off power to the charger?
Is rewiring only needed if the charger is going to be left unattended for some days (with the timer switching the charger on again at a predetermined time)?
Do you have any photos of your rewired timer’s internals?
That is good advice to avoid overcharging batteries.
I found this article which claims that “keeping energy levels between 20% and 80% can double your battery lifespan or better”.
https://electricbikereview.com/forum/threads/the-poor-mans-battery-saver-satiator-a-10-outlet-timer.22564/
Like you, the writer used a cheap 24 hour mechanical timer similar to this one from Amazon:
https://www.amazon.co.uk/Mechanical-Interval-Socket-Security-Programmable/dp/B01M8JWTAK
Can you clarify something for me please?
Is the timer to be used just as intended (set it for the charger to be on for a 4 hour charge, say) or is it necessary to rewire it internally
to guarantee switching off power to the charger?
Is rewiring only needed if the charger is going to be left unattended for some days (with the timer switching the charger on again at a predetermined time)?
Do you have any photos of your rewired timer’s internals?
Sorry, never took a picture....But this one shows how simple they are:-
The red bit is a microswitch that switches the mains on and off! The white thing in the bottom RH corner is the synchronous Motor. The top middle is the plug and socket arrangement, this one appears to be continental, not UK.
I love the first link you posted, it supports completely my thoughts with various different types of battery completely.....And which several people here have "aggressively" told me I was wrong!!!!!
THEY ARE WRONG IT SEEMS!!
The link for the timer is almost exactly the same one I have used for some years, that is the cheapest of the lot!!
If you are someone who can dismantle such a device, rewire it and put it back together in a working condition, its very easy.
Inside such devices are what is called a synchronous motor, a tiny one. Such motors synchronise themselves with the Mains frequency, so for the UK you need a 50Hz version, for the USA a 60Hz version.
In the 40s and 50s, there were many house clocks running on the mains and the electrical supply company had to maintain the exact count of the cycles each day, or these clocks would show the wrong time.
4,320,000 "Cycles" per day if I remember correctly.
It was allowed to vary slightly within the day, but by midnight, the count had to be exact.
Buy a timer with normal screws holding the case together, (the one you pictured has security screws, common ones that are easy to buy the tool on ebay for!
On some timers, you need a tiny Phillips screwdriver, but often today there are strange screw heads, that prevent you from opening completely, or need special screwdrivers (available on ebay).
The first picture shows a screw, that can be tightened by a normal screwdriver, but not loosened.
Its called a "One Way", and you need the same size special screwdriver to undo it. Its on the second picture top row. Try to avoid these screws and do remember, the driver has to have the same diameter as the screw, and might be down a "tunnel", that "bits" cannot go down far enough!
The cheap timer is basically exactly the same as those old clocks in most ways, though I might suggest that you run it on the mains for a few days to see that it is fairly accurate.....
Then simply open it up, find the wires that goes to the plug part and for the UK, chose the phase side, RH bottom, where in a plug the fuse would go and cut that wire, at the plug that goes to the clock motor and solder it also to the phase, but after the switch that controls the on/off of the timer. The timers are so cheap that I personally would not bother to fit a changeover switch to allow a normal timer function, I would simply buy 2 if you need that!
Put it back together correctly!
Mark the switch in some manner so you know its been altered with a permanent marker.
Test for functionality.
Use!!
If you have any further questions, just ask.
Regards
Andy
People keep reposting this utter bumkum, which keeps the myth propagating.
A timer is a good idea to make sure that you don't leave your charger on too long after you get the green light. You should always charge to 100%.
Each to his own ideas of myths, but the Battery University is an excellent, online source of battery common sense and knowledge with regard to most types of battery.
It has been very well known and very respected for quite a long time!
I have used it for more than 10 years, probably more than 15....!
Maybe you can post a similar study, taken by informed testers, which shows the opposite?
As other than some repeatedly unfriendly and ill mannered comments on this website, I have seen nothing believable to change my mind.
Opinions vary widely, and are often wrong!!
I am more than willing to read anything and everything with regard to batteries of all types, especially Li-ion!!
Andy
I turn my Ebike Chargers off when the LED turns green . The instructions with my Pro-Rider Flare mid motor drive says to leave it showing green for 1 hour . As it`s charging in a shed at the bottom of the garden it`s not always adhered to !
You should always follow the manufacturer's advice because they generally know what's in their products and how they work.
For anybody else in doubt about why 80% charging is not a good idea, here's an animation that shows how a typical ebike charging system works. They nearly all use what's known as "top balancing", which is what this animation shows. The exact values vary from battery to battery, but in principle, they're all the same. When any cell reaches a high level voltage, a transistor opens up a load resistor to bleed off charge while the other cells catch up. This happens until the total pack voltage is equal to the charger voltage. If you only charge to 80%, no load resistors will ever open and no balancing will happen u til your battery is completely borked.
That animation is an extremely simplified version of cell balancing when charging only.
It does not tell you even half the story and is only true if the charger charges some cells above 4.2 volts apparently!
I apparently have GOOD chargers, and several accurate meters and both of my chargers stop at exactly 4.2 volts!
As any good 36 volt charger should.
What do you think happens then? No 42.25 volts ever!!
Your little animation film was not covering this issue at all, nor does it cover any balancing done while USING or discharging the battery either......
This what really happens:-
The balancing circuit balances the voltages on each cell, it is not set at any particular voltage that MUST be achieved.
Think of two cells and their relevant load resistors as being a pair of scales, old fashioned ones.
It does not matter if you have exactly 1 kilo on each side or 1 gram, they are in balance.
Assuming that the scales are designed for a maximum of 1 Kilo (42 volts!).
But if one weight is HEAVIER than the other, a Robot comes cuts a bit off the heavier weight. Till balance is again achieved.
The balancing circuit will always balance to the lowest common denominator! That is the cell with the lowest voltage. But wastes power and increases heat in the battery!!
From here it shows how both types work:-
https://www.analog.com/en/technical-articles/active-battery-cell-balancing.html#
Active cell balancing is a more complex balancing technique that redistributes charge between battery cells during the charge and discharge cycles, thereby increasing system run time by increasing the total useable charge in the battery stack, decreasing charge time compared with passive balancing, and decreasing heat ...
Active Cell Balancing During Discharge - No Charger Connected!!
The diagram below represents a typical battery stack with all cells starting at full capacity. In this example, full capacity is shown as 90% of charge because keeping a battery at or near its 100% capacity point for long periods of time degrades lifetime faster.
30% represents fully discharged to prevent deep discharge of the cells. Over time, some cells will become weaker than others, resulting in a discharge profile represented by the figure below. It can be seen that even though there may be quite a bit of capacity left in several batteries, the weak batteries limit the runtime of the system.
A battery mismatch of 5% results in 5% of the capacity unused. With large batteries, this can be an excessive amount of energy left unused. This becomes critical in remote systems and systems that are difficult to access since it results in an increase in the number of battery charge and discharge cycles, which reduces the lifetime of the battery, leading to higher costs associated with more frequent battery replacement.
With active balancing, charge is redistributed from the stronger cells to the weaker cells, resulting in a fully depleted battery stack profile.
The animation does not have the circuit paths to do that!!
Furthermore, your comment here is so electronically wrong in all respects:-
This happens until the total pack voltage is equal to the charger voltage. If you only charge to 80%, no load resistors will ever open and no balancing will happen u til your battery is completely borked.
I have learned a new word!!
But none of the resistors "open or close" as you appear to believe!
Resistors are passive devices.
But the transistor can switch between "ON or OFF", either applying the resistor as a load across the cell or not! The state of the transistor is clearly marked as being on or off in the animation, not for the resistor, for the transistors, look at the animation again.
Or it can possibly switched to being a partial load, depending upon the way the control electronics are designed to work.
Which has not been mentioned at all!
If any of the load resistors were switched on, during charging as you imply, that cell would not be charged or only slightly! Depending upon the value of the resistor and the SOC of that cell!
Furthermore, apparently the animation is only of a very simple balancing system, probably not used that much today, if at all? As it simply "wastes" the power from any cell above balance voltage.
The transistor must be "OFF" for the cell to charge....
Good modern battery's electronics are far cleverer in both charge, idle and discharge mode than many think!
Please take particular notice of the sentence:- "full capacity is shown as 90% of charge because keeping a battery at or near its 100% capacity point for long periods of time degrades lifetime faster. "
This is exactly what an average charger is doing, even when the LED has gone green!
Which is exactly what I have been trying to tell some of you here for some weeks, to no discernible effects!
But I do hope now that cell balancing has now been made far clearer for you, though I also recommend reading the whole web link I mentioned before thanking me!!!
My impression is that you are not electronically competent, sadly. A fact not a criticism, but I will still do my best to help you when I can, but never forget just how much energy is in such a battery, and "letting the smoke out" can be a disaster in many different ways!
I have only covered a simple version here, various web pages cover the actions in full detail, but it will go over the heads of some here.....so not required!
Regards
Andy
None of that is relevant. Show me an ebike battery that uses active balancing! Nearly all ebike batteries only use top balancing. Have you ever looked inside a battery to see what a BMS looks like or studied how it works? If you had, you'd know that nearly every one is similar to the one in that animation with the same transistors and bleed resistors, except 36v ones have 10 channels instead of seven.
The animation is correct regarding the animation. It shows exactly what happens when we charge our ebike batteries. He's using a 30v charger, where as we'd use a 29.4v one. His BMS opens the load resistors at 4.25v. Ours normally open at 4.2v.
When the transistors open, they create a path between the top of the cell to ground through the resistor, so the charge bleeds through the resistor to gound. When the cell voltage drops below 4.2v, the transistor switches off. That's it. Really simple. It works the same as drilling a hole in a bucket near the top, so no matter how much you fill it above the hole, it'll always drain down to the same level. Put 10 such buckets in a row and that's our 36v ebike battery. The only way to balance is by overfilling and letting them drain down.
PS. I managed to find a BMS with those active balancing chips on Ebay. It costs £399, which is probably why you don't see them in many ebike batteries.
https://www.ebay.co.uk/itm/Evaluation-Board-Linear-DC2064-12s-active-battery-balancer-LTC3300-LTC6803-DC590/202554690560?hash=item2f29334c00:g:QWwAAOSwfTlcLJdb&redirect=mobile
The animation is correct regarding the animation. It shows exactly what happens when we charge our ebike batteries. He's using a 30v charger, where as we'd use a 29.4v one. His BMS opens the load resistors at 4.25v. Ours normally open at 4.2v.
When the transistors open, they create a path between the top of the cell to ground through the resistor, so the charge bleeds through the resistor to gound. When the cell voltage drops below 4.2v, the transistor switches off. That's it. Really simple. It works the same as drilling a hole in a bucket near the top, so no matter how much you fill it above the hole, it'll always drain down to the same level. Put 10 such buckets in a row and that's our 36v ebike battery. The only way to balance is by overfilling and letting them drain down.
PS. I managed to find a BMS with those active balancing chips on Ebay. It costs £399, which is probably why you don't see them in many ebike batteries.
https://www.ebay.co.uk/itm/Evaluation-Board-Linear-DC2064-12s-active-battery-balancer-LTC3300-LTC6803-DC590/202554690560?hash=item2f29334c00:g:QWwAAOSwfTlcLJdb&redirect=mobile
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It would be easier for me to understand what you are getting at, if you at least used the terminology of the animation, which refers to the transistors that "apply" the resistors, on and off!!
Your terminology is simply wrong and therefore misleading....
Your choice of course, but I see then no need to take any further interest in your imaginings......
Andy.
I'm only trying to help you.
Transistors are electronic switches. Two legs are like the in and out connections. When you apply a voltage to the third leg, it switches on. In the case of the balancing in that animation, the electonics detects that a cell has reached 4.25v, so it sends a voltage to the transistor on that channel. One side of the transistor is connected to ground and the other side is connected to a load (bleed) resistor. The other side of the resistor is connected to the top of the cell. That means that when the transistor is switched on, there's a path from the top of the cell through the resistor to ground.
The value of the resistor is normally around 100 ohms and it controls the rate at which charge bleeds to ground. Ohms law says thar the current will be 4.25/100, which is 45 miliamps. That's not very much. It would take 200 hours to drain a 9Ah cell group, which is why doing say one full charge in five isn't enough to balance your battery.
Transistors are electronic switches. Two legs are like the in and out connections. When you apply a voltage to the third leg, it switches on. In the case of the balancing in that animation, the electonics detects that a cell has reached 4.25v, so it sends a voltage to the transistor on that channel. One side of the transistor is connected to ground and the other side is connected to a load (bleed) resistor. The other side of the resistor is connected to the top of the cell. That means that when the transistor is switched on, there's a path from the top of the cell through the resistor to ground.
The value of the resistor is normally around 100 ohms and it controls the rate at which charge bleeds to ground. Ohms law says thar the current will be 4.25/100, which is 45 miliamps. That's not very much. It would take 200 hours to drain a 9Ah cell group, which is why doing say one full charge in five isn't enough to balance your battery.
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