There's no way that charger can work on a normal ebike battery with a BMS. When any cell goes below 2.5v, the BMS shuts off the charge port, so no clever charger can get anything through it.
If your battery won't charge, the first thing you do is measure the voltages on the charger jack and the battery's charge socket. Those two voltages will tell you where to look for the solution.
If eiether show 0v, yu should be looking for a blown fuse or wring issue.
If the charger shows full voltage, it's not likely to be causing any problems.
If the battery shows more than 0v and less than 20v, the BMS is switched off, so you have to open the battery and measure the cell voltages to find out why.
If you need to charge individual cells or groups, you can use a lab power supply, which can do everything you need regarding charging ebike batteries and it'll cost much less than that one above. This is the one I use. You can charge just about anything with it.
L Operation Frequency Range: 45 – 65HZ. l Efficiency (220Vac/full load): ≥ 87%. l Full Load Input Current (220Vac): ≤ 1.4A. l No Load Input Current(220V): ≤ 80mA. Load Regulation (0-100%): ≤ 30mV. l Output Current Range: 0 – 3A.
www.ebay.co.uk
You mentioned "If the battery shows more than 0v and less than 20v, the BMS is switched off, so you have to open the battery and measure the cell voltages to find out why." According to Texas Instruments, it is already too late at 20 volts, the battery is already damaged at these values, time to re-cell probably!
According to TI, in such a case of extreme low voltage of 2.4 volts or less per cell, a non reversible reaction takes place inside the battery. So the true lowest voltage acceptable for recovery, must be somewhat higher than 2.4 volts per cell, or 24 volts for a 36 volt battery!
Leaving some room for differences between cells, which also demands a higher voltage, for safety and reasons of recovery, must be assumed.
So the 20 volts you mention, is well within the zone of permanent damage to each and every cell, so it really is completely irrelevant if the BMS turns itself off as you claim! The damage has been long done to the cells!
My first battery, the one that came with the bike, would not charge from the standard charger and Stark sent me, on loan, a 0 Volt Charger.
He only had one at that time for such problems with delayed deliveries, now he sells them!
In my case, it charged immediately and recovered the battery, allowing the standard charger to work again, which it still does. I assume that my battery was therefore "above" 24 volts, or 2.4 volts on each cell still, as the battery has gone from strength to strength in use.
Sadly, I did not attempt to measure the battery voltage before charging, so at what level it was I cannot say, only that my normal charger would not charge it, and after the 0 volt charger had done its work, the normal charger worked perfectly and still does!!
Stark told me that the standard charger would NOT charge the battery if it went under 29.2 volts, if I remember correctly, its almost 3 years ago!
But I carefully observed what the 0 volt charger did, just for my own information, and its "almost" magic and very clever, but certainly not difficult!
If I ever hear of another battery in this state, I do believe that I could recover it without such a charger now, knowing what I know, and without even opening the battery.
But I promised Stark, to NOT divulge how it works, as its covered in the supplied document quite well, assuming that you are are an electronics "buff"!
But it does work!
I would imagine that any good bike shop would/should offer customers such a service on such a "down" battery, but the bad ones will probably simply try to sell a new, or to re-cell a battery.....
Trick question:- How to tell a good bike shop from a bad e-bike shop?
Answer, ask them if they have 0 Volt Chargers available for use on batteries that do not charge anymore...and If the answer is NO, find a better shop!!
Guessing only, but probably a great number of e-bike batteries have this problem each and every year, sadly, simply because the customer has treated the battery badly...and to a lack of good information from the suppliers and manufacturers...I have seen it over the years with Laptop batteries, exactly the same problems.
I fairly found an interesting dissertation from Texas Instruments about Li-ion batteries, with one particular sentence, supporting my own personal view of looking after Li-ion batteries.
I will underline that sentence for you below in these few paragraphs:-
LI-ION: HOW CELLS ARE DAMAGED
The biggest problem with the Li-Ion battery is the ease with which it can be damaged during use:- The Li-Ion battery carries a very large amount of energy in a small package. Combined with the fact that the internal resistance is fairly high, you have the potential for a very dangerous product:- If the cell is accidentally shorted, it could get hot enough to burn a user (and possibly explode).
The makers of Li-Ion cells handle the explosion threat by designing the case of the cell so that it will "die with honor", and not explode in some ones pants pocket if the battery hits their car keys. More importantly, the actual battery terminals are simply never allowed to reach the outside world.
The only manufacturer presently shipping Li-Ion batteries for consumer products does not sell single cells, only battery packs (Possibly a bit outdated).
Contained within the pack is circuitry that isolates the battery power leads from the outside world if excessive current is sensed, preventing battery damage and protecting the user.
Another easy way to destroy a Li-Ion battery is by discharging it too far. The Li-Ion cells should never be allowed to drop below about 2.4V, or an internal chemical reaction will occur where one of the battery electrodes can oxidize (corrode) through a process which cannot be reversed by recharging.
If this occurs, battery capacity will be lost(and the cell may be completely destroyed).
A similar process will occur if an Li-Ion cell is charged to too high of a voltage. If current is continually forced into a fully charged cell, internal corrosion can take place which will reduce cell capacity (possibly completely). For this reason, Li-Ion cells cannot be trickle charged for extended time periods without cutting off the current when full charge is reached. Sustained charge currents (even a few μA) can damage the cell if allowed to run continuously.
This "few μA" are exactly what many reasonably priced chargers still supply, in spite of the LED for full charge, showing green. They "trickle Charge", easily measured with simple equipment!
It is the reason that most chargers should never be left on charge, once the LED goes green. A point that I have tried to make here on pedelec on several occasions, to little or no effect apparently!
Furthermore, high current discharge rates reduce battery capacity, as do high charge rates.
Both should be avoided.
Andy
PS. I forgot to mention lifespan, this is from Wiki and I feel it explains a lot about the huge differences between some batteries:-
Variability
A 2015 study by Andreas Gutsch of the Karlsruhe Institute of Technology found that lithium-ion battery lifespan could vary by a factor of five, with some Li-ion cells losing 30% of their capacity after 1,000 cycles, and others having better capacity after 5,000 cycles. The study also found that safety standards for some batteries were not met. For stationary energy storage it was estimated that batteries with lifespans of at least 3,000 cycles were needed for profitable operation.
I had to laugh when I saw this, as I always estimated worse case, people leaving the charger on far too long, would be 2,000 to 2,500 charge cycles, where I myself got drastically more than that. Now I see that method of mine, actually supported IN PRINT!