Pie shutting down on start

[vapid2323]

I have a HP8204L3

Kinda like this:


It shows a Green LED when fully charged, and mine is showing just that

[GM Brazil]

If is the same as mine:


So this chrager dows not give any voltage when it is disconnected of the battery, when it detects the battery it starts to work.

Im having problems with my battery, so when the BMS kicks off the battery the charger does not detect the battery! So I need to manually move the wheel pedaling with my hands than use the regenerative braking, this activates the controller and then you turn on the bms. And also my pie does not have even 5km of range anymore.

I'm sure mine is a battery problem, but yours could be the charger or be like mine but worst. (at least I can go to the bakery)

[Leslie]

I just took my first reading, I am adding in the pictures so you can tell me if I did it correctly.. Also I cant seem to figure out how to read the amps, all I get on the meter is 000.

This is a reading after the Pie had ran for about 10-15 seconds (dont know if that matters)

Output of Charger: 53.1V
Output of batt while on charger: 48.5V

I will restate what Bikemad has posted before.

Test the voltage when it is charging and close to finish.  Does the charger light go red at all when charger is connected?  Test the voltage from the charger plugs on both sides when disconnected.

Test the volts from the charger unplugged, and the volts coming from the pack where you plug the charger in to see if there is a voltage to the pack for the charger,

Be sure not to connect the red and black wires when testing.

And the meter is not suitable for high amps.

[Leslie]

If there are good volts on both charger input plug and and charger output plug and you have no red light on the charger,  Leave it plugged in over a whole night and try the bike late in the morning.

Post all voltages I mentioned before this post.

This is not how it should be but you can charge the pack slowly like this and it is a good idea to leave the pack on float charge while you await a possible replacement charger.

[vapid2323]

Does the charger light go red at all when charger is connected? Yes, the red light never turns off unless the charger is off
Leave it plugged in over a whole night and try the bike late in the morning. Still Showing 48.5V
Test the volts from the charger unplugged. 53.1V
see if there is a voltage to the pack for the charger. I do have Volts
volts when the charger shows a yellow light.. The output of the battery will slowly increase has it gains more charge, data dosent seem usefull

I am not the best with electrical things but my guess is that my battery is bad not the charger?

[vapid2323]

Is the charger finished charging befor you take it off the battery?

Yes I get a green light before disconnecting the battery

[Leslie]

see if there is a voltage to the pack for the charger. I do have Volts
volts when the charger shows a yellow light.. The output of the battery will slowly increase has it gains more charge, data dosent seem usefull

I am not the best with electrical things but my guess is that my battery is bad not the charger?

My bad I asked the wrong question.  I am very sorry to put you through more tests.  I thank you for your patients.

I am trying to post for you to understand yet I understand not much of the charger.  Yellow green and red.  My charger has green yellow and red. and red means its charging not yellow.

Ok the battery is charging when yellow light is on and the battery rises until it goes green.

You would be sure that the charger is charging the battery?  SO your charger is working.




Ok next question..  this is important



When the motor cuts out is there any volts from the battery from the motor/controller connection?  or is the battery not giving volts to the motor/controller and the battery management system (BMS)  has cut the power from the battery to the controller.



Test.


Connect the probes so you can measure the volts from the battery when the controller is connected and turned on.  Y.  If you get volts from the battery socket on the pack when the controller is switched on, place your probes into the battery socket holes to test and do the following.

See the voltage 53.1v, twist the throttle and watch the volts.  Do they drop fast and motor cuts out?

[GM Brazil]

He should have the same charger I have.

Two leds
One red that does not change color, it is only a power on led.
Second led is orange, or yellow, when charging, green when charged and off when the battery is not connected or the charger does not detects the battery (my case)

[Bikemad]

See the voltage 53.1v, twist the throttle and watch the volts.  Do they drop fast and motor cuts out?

If I've understood the test results correctly, it's only the charger voltage which is 53.1V, as the battery voltage does not rise above 48.5V (even during charging).

To me, this indicates that the BMS is not allowing the charging voltage to reach the battery, and the battery is therefore not being charged.

Unfortunately, the green light coming on does not necessarily mean that the battery has been charged, it just signifies that the charger output has risen to a pre-defined maximum voltage, combined with minimal (very low) current draw.
This would usually occur only when the battery is fully charged, but it can also happen if there is a poor or open circuit between the charger and the battery.  
In this case the break in the circuit will be somewhere on (or connected to) the BMS.

If this battery was purchased direct from GM, an email will need to be sent to Tom (zhourenli@goldenmotor.com) explaining that the charger appears to work correctly, yet the battery remains at 48.5V and is not receiving any charge.

Alan
 

[Leslie]

I do have Volts
volts when the charger shows a yellow light.. The output of the battery will slowly increase has it gains more charge, data dosent seem usefull

I am not the best with electrical things but my guess is that my battery is bad not the charger?

I think the battery is charging.  His English skills are making this a little difficult.  I am still confused as to whether the charger is working or not.

Data doesnt seem useful.

 

What does this mean?

We will get to the bottom of this.

[Bikemad]

I think the battery is charging.  His English skills are making this a little difficult.  I am still confused as to whether the charger is working or not.

His English is on the whole pretty good, and I don't see how you can misinterpret this statement:

Output of Charger: 53.1V
Output of batt while on charger: 48.5V

I therefore assumed that the charger is working, but the battery is not being charged.

Alan
 

[Leslie]

I do have Volts
volts when the charger shows a yellow light.. The output of the battery will slowly increase has it gains more charge, data dosent seem usefull

Yes but
 


He says here he has a yellow light here and the battery voltages rise when the charger charges. Or does he?

LiMn cells:

4.2v hot, 3.8v nominal and 2.5v discharged.

54.6/4.2v=13 cells.

13cells x 3.8v = 49.9v nominal.

13x 2.5v =  32.5v

32.5v = empty pack.

48.5v is not an empty pack.

Why is his battery BMS cutting out at 48.5v?

There is more to it I think.

I would assume the same if his battery was not going up in volts.  I do assume its the BMS but I don't want to submit to this possibility just yet.

I have never owned an LI battery and I just go on what I read here. I'm scared to ask the question again you know.

[GM Brazil]

I vote for damaged cells. It can explain the low maximum voltage and high voltage drop during any load!

[Leslie]

I vote for damaged cells. It can explain the low maximum voltage and high voltage drop during any load!

Yes this is what the test with voltage probes on pack when twisting the throttle looking at the voltmeter is for.

I was thinking it could be a short in the motor drawing excessive current.

I do believe the controller has a safety off function for a few things too, overheating and other stuff.

He must rule out the charger, BMS or cells first.

Another test is a load test.

4X 15v 150 watt halogen bulbs in series.



Place four of these in series between both pack output terminals and use an amp meter to test load, These draw almost 15 amps and output almost 600 watts on a full pack,  You only need to test for 5 minutes or so. More than 45 minutes and the battery may LVC.  All lamps will get very hot so be careful.

This can work as a capacity test too.

With no controller connected and lamps placed over the terminals, the above test will weed out the bad packs from the good ones with no problems or chance of mistakes, providing human error is not any cause of failure.

The above 15 amp load test will test everything from the pack battery output, BMS, and detect possible battery terminal or cable intermittent failure.

I find dry joints in old TV's and stuff by tapping the operating circuit board gently with the plastic butt of a screw driver and observing the screen in a mirror.   A singe flicker or noise crackle from the speaker and I mark the area of the PCB I was tapping and resolder the area.

I would do similar tests on an intermittent controller to see if a bumpy ride would cause me grief.

[vapid2323]

Ok let me try and clear things up...

Originally I never had a volt meter, for instance when I recorded that video I had no way to test the volts.

When fully charged I only show 48.5v on the battery connectors (also the charging port shows the same number)
The output of the Charger itself is 53.1v (I don’t have a way to test if this is the same when connected to the battery)
While the battery is charging the outputs will show the battery’s current voltage, for example is will start at 40v and slowly increase over time to 48.5v.

I love the test idea with the lights but I don’t really have the time to do that.

I don’t believe it’s the Pie, as I am able to ride it up hills and really push it without it over heating or cutting out (hell I am 260lbs) the issue seems to show up because of the drop in voltage and because I am not receiving a full charge so I am only able to ride for about 1 mile before running into issues.