Intro

[Chrispick1977]

Hi all I'm Chris from Yorkshire, I have minimal electrical experience and am really after some advice on my children's 24v ride on car. 

It's fitted with a 24v battery which really doesn't seem to last long. Since I happen to have a spare 12v battery I wondered if I could link them up so it would last a bit longer. What I don't want to do is make 36v and burn the motors out. (would it?). 

I've researched a little and think I want them "in parallel" hut would like a bit of guidance if that's possible please. 

 

[Geoff1946]

NO. You'll break it!   You can only parallel batteries of the same voltage, and also preferably the same type. Don't put them in series either, as you have already worked out what will happen.

 

[SPECIAL LOCATION]

Hi all I'm Chris from Yorkshire, I have minimal electrical experience and am really after some advice on my children's 24v ride on car. 

It's fitted with a 24v battery which really doesn't seem to last long. Since I happen to have a spare 12v battery I wondered if I could link them up so it would last a bit longer. What I don't want to do is make 36v and burn the motors out. (would it?). 

I've researched a little and think I want them "in parallel" hut would like a bit of guidance if that's possible please. 

It can help to think of the Voltage as the "pressure" that will push the electricity around the circuit.. (e.g. to the motors)..

And similar to water, if you have two sources of pressure and one was double that of the other...

First of all they will try to become equal.. i.e. basically your 24v battery would be trying to charge the lower voltage battery...

and the 12v will end up draining chunks of power away from the motors you are trying to supply...

What you probably need to look at is a higher capacity 24v battery...

Somewhere as well as the voltage it will say how many Ampere Hours  (Ah) it is rated at..

(i.e. if your car consumed 5Amps each hour of continual use, a 10Ah battery would allow 2hrs of operation)

Or an example using 12v Golf caddy batteries...    Three typical options shown here are 17Ah or 24Ah or 38Ah..

https://www.hardwarexpress.co.uk/yuasa-npc-battery-range-280-c.asp

so the 38Ah battery would last double the duration of the 17Ah one before it needs recharging.

I think you need to start by identifying what the Ah rating and physical dimensions of the current battery are...

then see if you can find an equivalent size 24v battery with more Ah.

(Two identical 24v batteries to you original item connected in parallel should give approx. double the duration).

Guinness