I've noticed with the older SANS chargers the voltage from the factory is around 41.7V or less. Assuming you have a calibrated DVM and you really are getting 41.5 V, then it's unlikely your pack will ever get into balancing mode, which seems to need at least 41.8V for a 10s pack.
Batteries Charging Routine
- Thread starter Az.
- Start date
This thread may be of relevance, where I had a look at what happens when increasing the charging voltage step by step.
www.pedelecs.co.uk
Monitoring the Balancing of a Pack
Been meaning to post this for some time but not got around to it so here goes while I have a moment spare. I think it's worth looking at as the results are quite interesting. I posted this back in November last year: Here is a dismantled Yose power pack, generic Chinese cells, crappy 20A BMS...
www.pedelecs.co.uk
On my SANS charger, the voltage is 41.5V to 41.3V when charging is finished.
I have never felt concerned with how long to leave the LED on green before switching off the charger. It could be as soon as it goes green or the next day.
At work, we don't get to sort out many battery problems for the last 3-4 years now. I haven't personally found a single out of balance battery in the last 4 years. The typical fault is when someone sticks the key into the jack charging socket, we have to replace the charging socket. Another common fault is the output connector on the rack batteries need replacing.
I still want to know what would come out as best practice from collective experience of forum members but that's it. I had used a Bosch tool battery on my Brompton for a while but replaced it with a 10AH bag battery. The penalty in weight is imperceptible and I stopped worrying about running out of battery.
As far as I can see, if you buy a battery from a reasonable supplier these days, the production technology for cells has become so consistent, that they rarely go out of balance. I think 10 years ago, it would have been a different story.
I am more worried about a dodgy BMS causing imbalance by discharging one or more banks due to a fault, as has been reported for certain makes.
the BBC is doing a substantial reportage of battery fires this morning.
I think batteries and chargers will need certification soon. Even so, there are still millions upon millions of dodgy batteries and chargers out there.
I think batteries and chargers will need certification soon. Even so, there are still millions upon millions of dodgy batteries and chargers out there.
Who gave that diagnosis? Rather than blame the customer, you might want to do something about your incorrect charging instructions, which would cause that fault.
It's a weakness in the design. The jack charging socket is placed on the opposite side of the keylock.
People use the key to remove the battery and stick it in the charging socket instead. Big spark follows. Only 3 or 4 cases in the last 4 years. I will post a picture later.
People use the key to remove the battery and stick it in the charging socket instead. Big spark follows. Only 3 or 4 cases in the last 4 years. I will post a picture later.
A bit like the problem when people fumble around the rear of a lap top to plug in a USB A, only to find to their cost that it's been designed to neatly fit into the RJ45 connector, blowing that.
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they told us what happened, one moment of lapsed attention. There is a cover for the charging port but they forget to put the cap back now and then. They don't need a manual to use the key or to remove the battery, and each bike comes with already 4 manuals, I can't fix that with more manual.
It's not because in this case you can't get the key far enough into the socket to short the pins, not unless you did it intentionally, even then, it's not easy. As I said, the problem is caused by incorrect charging instructions, not from wayward keys.
All of them and it's a "typical fault"? It's a bit weird that nobody has ever mentioned that on this forum before, especially when it's virtually impossible to do. Did you try it? I did! In fact, not only did I try to get the key in the socket, but I also previously tested your charging procedure. The result of the charging procedure was the jack welded to the blade in the socket,and a big flash and bang when I tried to remove it and most of the socket got vapourised, then the need to replace the socket.
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can you be a bit more precise? which manual are you looking at? There are dozens on the manual page.
talk to Andy about it. He's the one who told me this morning because I asked him (what kind of faults did you see in recent years, did you rebalance a battery recently?) for this thread. I have not repaired any battery for years. The batteries we retire are simply old, not dead. I don't throw anything away but Hatti does.
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It's probably all of them going back to lead batteries. I only looked at your SWX02 kit one and one very old one. I think somebody just cuts and pastes.. You need to check. It's only a problem with the 5.5mm jacks. You'd get a spark on some of the others, but it would take a long time to erode the pins.
with a key, you get a big spark, a smell of burning and a blackened socket. Customers ring up. We ask for pictures and if we find any damaged plastic or pin, we retrieve the battery and replace the connector. It doesn't happen very often but still does now and then.
