Charger problem

[Onetom2]

I mailed Tom for asking for a new charger because the Goldenmotor charger was defect.
So far nothing from GM.
I don't know if GM has some kind of warranty for people who buy there stuff.
So if you thinking about buying things from GM, go to a GM dealer and not from the internetsite.
So when you've got problems, you can go to the dealer in youre own country.
Greetings, Henk

Thanks Henk. As soon as I mentioned a replacement charger Tom changed the subject and said it could be the battery pack? Oh the variables of cutting edge technology how fickle.
I think that goes without saying judging from posts across this forum. I have been reading up because I can't find a dealer in Australia. What looks like their product is not necessarily being advertised as such. Do you know if anyone has succeeded in finding a website for these guys who build the chargers: Sans Electronic Co., Ltd. Building No. E, Industrial YanDai, Battery Charger (Li-ion Battery Charger)SSLC084V42 ... Seems all the lights are on but nobody home?  Since the pulsing charger with red LED and relay noise was actually charging but when it stopped pulsing the voltage wound down to zero (no green light) I decided to put the charger on a 24 hour timer with 30 minute intervals. I gradually built up the volts in the pack to 37.5 but I noticed on a short run that twisting the throttle killed the green LED on the battery indicator, which came back on when I released the throttle. I am not very keen on doing any distance and end up in the middle of nowhere with a flat battery again. I can't see this battery lasting long with 20+ charge cycles to fill it. One of those Ikea timers has died already. It seems the most frequently used description from one end of the kit to the other is dying died snuffed it or is very dead...disturbing to say the least? I have run out of pocket money for a while the analysers seem to be the next logical step. One for the bike and one for the workshop that has a USB connection to my PC. If anyone else has used one of those maybe thay can share their wisdom with us?
Cheers onetom2     
 

[Henkav]

Hi onetom2,

You wrote "Thanks Henk. As soon as I mentioned a replacement charger Tom changed the subject and said it could be the battery pack?"

He asked me to send some pictures.
I still dont'n know why?

Greetings, Henk

[Onetom2]

Likely this is a source of entertainment. Or perhaps he wanted to compare cameras since I sent him one to request definition of instructions...the wires are different colours and different labels to what he wrote?
I debated with myself for a couple days over his request for me to open my battery pack and do some voltage reading since breaking the seal on the battery pack where I come from was an immediate void of any warranty. But then I realised just the manner of communication had more or less ruled out any such guarantee. As you so aptly pointed out a dealer in Australia would have been the best warranty but I didn't expect to have this much trouble the widespread use of electric bikes in China and the impression of s company with a global market. It was only after experiencing problems right from the start I was reminded of a conversation about the technical complexity of Lithium Phosphate4 chargers a couple of years ago. The down to earth engineer telling me to steer clear since the chargers were such expensive pieces of electronics. Obviously the GM charger isn't.     

[Bikemad]

I gradually built up the volts in the pack to 37.5 but I noticed on a short run that twisting the throttle killed the green LED on the battery indicator, which came back on when I released the throttle. I am not very keen on doing any distance and end up in the middle of nowhere with a flat battery again. 

Tom, your battery pack consists of 40 x 4Ah cells, configured as 10 groups of 4 paralleled cells, which are then connected in series to produce a nominal voltage of 38V with 16Ah capacity.

If your pack is only being charged to 37.5V, that's only 3.75V per cell, so your pack is already 95% discharged before you even set off!
You're not going to go very far using just the last 5% of your battery's capacity (approx 0.8Ah), and it's not recommended to completely discharge the battery pack if you want to maximise its life expectancy.

Your battery should be almost 42V when it is charged correctly, and until this happens, I would recommend you try not to use it.

The following diagram shows a typical discharge curve for a Lithium Manganese cell, which should give you a rough indication as to the current level of your pack.



I do hope Tom (GM Tom) is able to sort your problem out soon, as it must be extremely frustrating for you.

Alan
 

[Onetom2]

Thanks Alan.
Thank you very much for that confirmation of pending disaster. I made the original mistake of riding the bike unaware of the chargers inability to charge as the indicators gave me all lights on. But I suppose I was actually taking the battery down to empty with no clear indication until the very last gasp and the lights went out. I wanted those extra volts but worried about the short bursts of battery relay pulsing that could run from 5 10 or even 20 minutes and then stop not knowing the long term effect on the pack. I had been checking those 10 wires over and over day after day with .5 of a volt gained every so often. Judging from what has been said on this forum the likelihood of paying for a charger to be sent out that actually works is "Pie in the sky" (did I say Pie?) I have a mini actually. I concluded I was not going to risk an attempt at any distance records until I had an analyser on board. That could be months away on my pension budget. Its a funny thing that I can't explain but I don't get frustrated nor waste emotional energy any more. I sincerely appreciate your input Alan, Its the basic laws I am totally unaware of and I am working blind. There seems to be nothing useful available in Australia regarding concrete practical knowledge in this area, those who might know are not about to divulge their knowledge, its currency.
The pack strings appear to be OK albeit charging staccato style. I guess the theory is throw some more money often enough and your bound to strike lucky eventually? Thanks for you sympathetic words.
Onetom2
Tom