36V charger issues

[Functional Artist]

We have been having problems with Desteny's kart.

https://www.youtube.com/watch?v=qTRA1FXz9Lw

We got it out a few days ago & it wouldn't do anything.

The power switch was on so, I think she forgot to turn it off the last time we ran it.

I assumed the batterys were completely drained.

So, I hooked up the 36V battery charger that came with the scooter I got the motor & controller from. (used several times)

When I hook it up (to the bat pack) the light is green (to show connection) & when plugged in (to the wall) the light usually turns red (to show charging) & then turns green when done charging.

This time when I hooked it up the light stayed red (I assumed it was charging) but, it never turned green. (after a few hours)

This made me think the battery's were charged & there was another issue.

So I checked the fuse, motor, controller & throttle. (all checked out OK)

Maybe the battery charger stopped working.

(remember the lights didn't act right)

Back to the battery's.

So, I unhooked the battery's to check them individually.

Using a HF meter, (2) battery's checked out @ 12V-13V the other one tested @ only ~9V.

Hmmm... undervoltage protection built into controller must have did it's job.

This one of the first electric powered kart's I built & I just noticed that I used the wrong battery's.

(At the time, I had some lawn mower (starter) battery's (not deep discharge) so I used them.)

I charged up the low battery & it seemed to have went back to 13V but, the next day it was back to 9V. (I guess I killed it)

My question is... could this situation damage the charger?

Here is a video with more info.

https://www.youtube.com/watch?v=xFZrTK-3WOA

 

[itsid]

9V battery is very likely dead!

a car battery should never drop below 10 IIRC.. the 12V battery will prevent the other one from charging properly in series.. (internal resistance and stuff)

Sooo, easiest way.. try to charge the 9V battery seperately with your car battery charger (12V)
best: do the same for each individual battery and when done, connect them all in parallel over night to have them levelled out before you reinstall them in series.

With a bit of luck the 9V cell can be revived... chances are it's dead though.. you'll find out if you car battery charger isn't able to recharge it.

I've heard rumors about you could eventually revive it with a high amp boost from -best- a buck converter and some say they did the same with a short burst from a stick welder... frankly that doesn't sound sane or safe... but if you're brave enough you might want to give it a try.

'sid

 

[Functional Artist]

9V battery is very likely dead!

a car battery should never drop below 10 IIRC.. the 12V battery will prevent the other one from charging properly in series.. (internal resistance and stuff)

Sooo, easiest way.. try to charge the 9V battery seperately with your car battery charger (12V)
best: do the same for each individual battery and when done, connect them all in parallel over night to have them levelled out before you reinstall them in series.

With a bit of luck the 9V cell can be revived... chances are it's dead though.. you'll find out if you car battery charger isn't able to recharge it.

I've heard rumors about you could eventually revive it with a high amp boost from -best- a buck converter and some say they did the same with a short burst from a stick welder... frankly that doesn't sound sane or safe... but if you're brave enough you might want to give it a try.

'sid

Didn't help!

Nope! it's done.

Ya, Hit with a stick welder?

NOOOOO, I'll pass.

I'll get proper batteries for Desteny's kart.


My question was could that situation have damage the charger?

I tried using it to recharge El Dingo.

That's when I actually noticed that it was not working.

 

[Bbqjoe]

You won't hurt the charger.
Some chargers will continue to show a red light if the batteries are shot and won't accept a charge.
Sometimes, overcharging (boiling) a 12v battery to around 15 volts for an hour or two will loosen the build up between the plates which causes and internal short in a battery.
After an equalization charge always remember to top the battery back up with DISTILLED water. It might hold a charge, it may not.

Most times though, this is more appropriate for a deep cycle battery since the plates are much more substantial.

 

[ML-TOYS]

I usually get into safety fights about the dangers of not using sealed lead acid batteries (sla).

One tip rollover or crash has the potential of splashing acid all over the driver.

I have been called names, told to shut up, that i dont know what i am talking about, this is the biggest debate i ever got into with all my years dealing with power wheels.
One of the most common i got.
"So I put a car battery in my kids jeep, dont tell me whats safe for my kid"
I prefer safety of kids.

A couple people actually admitted to slight acid burns on their kids.

 

[Functional Artist]

I usually get into safety fights about the dangers of not using sealed lead acid batteries (sla).

One tip rollover or crash has the potential of splashing acid all over the driver.

I have been called names, told to shut up, that i dont know what i am talking about, this is the biggest debate i ever got into with all my years dealing with power wheels.
One of the most common i got.
"So I put a car battery in my kids jeep, dont tell me whats safe for my kid"
I prefer safety of kids.

A couple people actually admitted to slight acid burns on their kids.

Wow!

It seems like some folks & common sense never met.

Luckily, the ones I tried were sealed.

Yes, I agree safety always comes first.

I have rolled a kart before.

It wasn't fun.

Low center of gravity & a roll bar are #1 & #2 on my list of priorities when designing a kart.

My rule of thumb: Your behind should not be higher than the rear axle.

 

[Bbqjoe]

My rule of thumb: Your behind should not be higher than the rear axle.

That makes sense. Lower might give a whole different meaning to scrub brake.

 

[drm]

get qty (3) 1-5A maintainer chargers and charge the batteries separately. From my experience, the batteries will last much longer. You can also use the chargers for other battery toys (12V, 24V, 36V, etc.)