Electric Scooter Battery/charger malfunction

[RoboWanabe]

Hi There

Could one of you kind sirs please help me.

BackGround
I'm trying to Fix my nephews scooter, which after charging the recommended amount of time (8hr), seems to be loosing charge within 10 minutes of use.

The problem I think is that my sister has got the charger mixed up and has been using the wrong one, but i'm not to sure about batteries and charging so could do with some help please.

Information
The battery is:
SEALED LEAD-ACID BATTERY
CB4.5-12 (13v4.5AH/20HR)
CONSTANT VOLTAGE CHARGE
Cycle Use = 14.0-15.0v 77F(25c)
Standy Use = 13.5-13.8v 77F(25c)
Initial Current: Less than 1.35A

The charger is:
Model:HGIL240040 ( Was blured when reading this could be wrong)
Input:AC 230v -5hz 18w
OutputC 24v 400ma

Finally
Could someone please tell me if we are using the right charge? my guess is not. I cant see why you would need 24v to charge a 12v battery.
And Could any one please give an explanation on what some of the terms above mean (e.g. cycle use, standby use, inital current).

What is the general rule or method of charging a battery? can you point me to a good tutorial?

Thanks you so much for your help

 

[ronv]

Unless there is more "stuff" in the scooter to control the charge that is the wrong one.
This link has several methods to charge SLA batteries.
https://www.powerstream.com/SLA.htm
Cycle use is like a quick charge, standby is like a float charge it can stay on for a long time.
Initial current is the maximum they recommend to charge at.
Hope the 24 volts didn't toast it.

 

[ronsimpson]

The scooters I have repaired have two 12V batteries. And use a 24V charger.

 

[RoboWanabe]

Thanks guys.

Ronv i've been going through your link thank you its very informative. I now no that unless the charging circuit ( which i forgot to look at and mention) reduces the voltage down the an accecptable level, from what i gather this is between 13 -15v.

Ronsimpson. Now with two batteries at 12v with 24v charger did make sense but since I've read the link above it seems to me that the charger would need to be higher than both voltages combined say 25 - 27v

 

[ronsimpson]

seems to me that the charger would need to be higher than both voltages combined say 25 - 27v

The batteries says 12V and the charger probably says 12V but we know it must charge at "25 - 27v".
This is like a car battery "12 volts" but it is 14.5V when the engine in on.

 

[RoboWanabe]

OK I made a boobie

It appears there were two batteries in parallel ( One was hidden away dohhhhh).

I'm not sure on how to fault find with batteries but the readings I have taken are as follows:
- When charging the batteries they are at (bat 1-14.92v) (bat 2-14.57) and together they are (29.5v)
- When charger unplugged the batteries are at (bat 1 - 13.3v)(bat 2-13.2v) and together (26.4v)

So when I use the scooter it only last roughly 5-mins and loses power.

What more tests can I do to find out why it's not lasting that long?

Thank you

 

[audioguru]

Two 12V batteries in parallel produce 13.2V. Two 12V batteries in series produce 26.4V.

The charged batteries power the scooter for only a few minutes so their capacity is very low, or the motor or speed controller is defective.
Maybe the batteries were run down until their voltage became too low. Then their capacity is destroyed.
Maybe the batteries were stored uncharged. Then they became sulphated and their capacity is destroyed.
Maybe the batteries are older than 4 or 5 years? The battery in my last car lasted the longest at 6 years.

 

[RoboWanabe]

Thank you audio guru

I did know that, i must of had a blonde moment :O

Do you know of any way i can check the health of the batteries?

For e.g. if I turn the scooter on and test the batteries current and voltage what should I be looking for?
should the current and voltage be as stated in the OP

 

[audioguru]

A lead-acid battery in good condition can supply enough current to cause it to explode so DO NOT try to measure its maximum current.
The spec's for this little battery says 4.5Ah at a 20 hour rate so it should supply 225mA continuously for 20 hours. It might supply 20 Amps for a few minutes.
Hey! Maybe the scooter is made for a lightweight little kid, not for a heavy adult.

 

[RoboWanabe]

haha i have been scooting around on it how did you know
It was doing the same for him but he got about 10 minutes on it.

Where did you get the 225-ma from please ?

 

[ronsimpson]

I have repaired and sold too many scooters.
The first thing I do is replace the batteries. I get internet batteries at 1/2 of the store price.
Some times they come with a missing charger.
They never have good batteries.

 

[audioguru]

4.5a

Where did you get the 225-ma from please ?

The battery spec's say, "4.5AH/20HR" which is 4.5A spread out for 20 hours. Then the continuous current can be (4.5A/20=) 225mA for a total of 20 hours. It might provide 4.5A for 15 minutes.

 

[RoboWanabe]

I would prefer to just confirm that the batteries were broke before i decide to replace them

 

[crutschow]

After the batteries run down, check their voltages after about 3 hours of resting. The open circuit of each will give an approximation of their amount of charge as shown here. If one battery has a significantly lower voltage then it is likely bad.

 

[EinarA]

The OP has undoubtedly found a solution by now but since I use one these scooters my self I will weigh in. You should look for batteries specifically meant for electric vehicles; the Panasonic batteries in mine are more than 15 years old but still get me everywhere I want to go. ( I suspect the reason RonS's batteries are half price is that they are general purpose ones that will not last very long.) The charger should be a two step variety: i.e. One that switches to the lower float charge voltage when the batts are fully charged. Leaving them on the higher voltage for extended periods slowly decreases their capacity.