Adding another battery.....

[OxygenJames]

Hi there. I bet one of you can answer this real quick....

I have an electric scooter I just bought - first thing I did of course was take it apart to see how it all fits together. Like you do.

So it is 24V. It has two batteries and the four wires from these go separately into the controller - so thats all four separately go into the controller. Now.... say I wanted to extend the range a bit..... and wanted to add one more 24V battery. I assume once those four wires disappear into the controller - they join inside so that the two batteries are in parallel - yes?

So if I wanted to add another battery (to give me more range) - I could simply add it to one of the batteries - so you'd still have four wires going into the controller - two from one battery and the other two having two batteries (in parallel) attached. Would that be OK? Or would that be a problem?

Any thoughts?

 

[Deleted member 4366]

You should have a look in there to see whether they pull off 12v from the middle so you know which side to add your third battery. I guess that if you add it above the other two, it shouldn't matter.

 

[Alan Quay]

Hi there. I bet one of you can answer this real quick....

I have an electric scooter I just bought - first thing I did of course was take it apart to see how it all fits together. Like you do.

So it is 24V. It has two batteries and the four wires from these go separately into the controller - so thats all four separately go into the controller. Now.... say I wanted to extend the range a bit..... and wanted to add one more 24V battery. I assume once those four wires disappear into the controller - they join inside so that the two batteries are in parallel - yes?

So if I wanted to add another battery (to give me more range) - I could simply add it to one of the batteries - so you'd still have four wires going into the controller - two from one battery and the other two having two batteries (in parallel) attached. Would that be OK? Or would that be a problem?

Any thoughts?

You really need to look in there. If the batteries are 12v each, and the controller wants 24v then they will be in series, not parallel.

If that's the case, then to increase the capacity you will need two more batteries, each parallel with the existing ones. If you only put one in, then the single battery will be exhausted just a quickly as before.

As D8veh says, it may also pick up a 12v from the centre, so just throwing 24v at it with two wires probably won't work.

 

[OxygenJames]

OK thanks guys - currently both batteries are 24V - I can't see how I can go much wrong by wiring another battery in parallel to one of those - I was thinking in fact to wire two in - both in parallel - one to each of the batteries already there - and wire in a switch so if and when the power starts to drop I can bring the two new batteries on-line. If it blows up I will let you know.

One other thing - I have bought a new throttle because the one on there seems to be just ON/OFF in its functionality - there's no middle ground. But the current throttle has four wires going into it from the controller - the throttle I have bought only has three. I can't see why a throttle would need more than two wires personally - surely all it is is a fancy variable resistor (I am thinking scalextric here) - so surely only two of the wires actually do anything? Any thoughts on that please let me know too.

Cheers.

 

[OxygenJames]

I will check on those batteries though - on second thoughts maybe its two 12V wired in series - but I could have sworn they were both 24V. I will get back to you.

 

[Deleted member 4366]

The throttle needs three wires because it's a hall sensor. Two wires give it power (red 5v, black 0v) and the third tells the controller how much mpower to give. Did your last throttle have LEDs on it to show the battery charge. If so, you need to measure the voltage from the black wire to all the other three to see which is which. Do not try and guess because if you get it wrong, you'll wipe out your new throttle.

There's nothing to stop you doubling up both batteries, but you can't do it with a switch. Also, you must not connect them in parallel until they're at the same voltage (measured). That should be OK if you charge up both batteries before connecting them in parallel.

 

[OxygenJames]

Thanks. OK I get the thing about no switch as they have to be at the same voltage when joined - great.

On the wiring:

Currently the wiring is as per the picture attached - four wires coming out of the controller - Red (goes to an orange) - two yellows (one goes to another orange the other goes to a brown) - a green (goes to the other Brown). Beats me. Any ideas?
The new throttle has red black white.

So how do I wire up those 2 yellows and the green and red coming out of the controller to the red black and white of the new throttle?!!

I know you can figure this out.

 

[OxygenJames]

OK - this might help (sorry focus not great) - inside the old controller are two switches. One connected to the two browns - the other to the two oranges. When the throttle is shut off the switches are positioned so that there is no connection between the two oranges or the two browns. As you open the throttle one switch is activated which connects the two orange wires - opening the throttle further connects the two browns.

Could this work as a two-step speed control? The oranges when connected fire up half the juice and then at full throttle the browns connect which then brings on the other power? And could each set bring on one of the 12V batteries.

In which case I am not sure my new throttle can be wired up at all.

Thoughts anybody?

 

[OxygenJames]

OK. Update. It is NOT a two-step control. Its on and off. If you just connect the two oranges (ie joining the red and one yellow from the output of the controller) - NOTHING HAPPENS. If you then connect the browns (ie joining the green and the other yellow from the output of the controller) - BINGO - it comes on. But if you connect the browns without the yellows already connected nothing happens.

So - my conclusion so far (I hope you're all paying attention at the back) - the red and the yellow have to be connected - so they must be some sort of cut-off switch? Once they are connected you can join up the green and other yellow and Power comes on.....

I am still not completely sure how I now wire up my new throttle which has three wires.

Stay tuned and any thoughts welcome.

 

[Deleted member 4366]

If I were you, I'd get a new controller. They don't cost much. The one you have might not have the correct software to work from a conventional throttle signal. I reckon that you have a two stage throttle, but one stage doesn't work for whatever reason.

Is it a stand-on scooter or what?

 

[OxygenJames]

Yes its a stand on scooter. 24V. Do you know where could I get a controller from?

 

[OxygenJames]

Do I want a brushless or brushed one? How would I know?

 

[OxygenJames]

How about this - would this work?

http://www.ebay.co.uk/itm/24V-350W-Speed-Controller-Black-Box-Electric-e-Bike-Scooter-/171631851214?pt=LH_DefaultDomain_3&hash=item27f60e36ce

 

[Deleted member 4366]

How many wires connect the motor to the controller? Two means brushed, more than two means brushless.

If your scooter uses an R/C motor, it might use a different type of controller altogether. We need a lot more details to say. Show us some photos of your controller and motor.

 

[OxygenJames]

Please see pics. Plus - I see I could upgrade to a litihium battery - see here:

http://www.ebay.co.uk/itm/131398664626?_trksid=p2060778.m1438.l2649&ssPageName=STRK:MEBIDX:IT

Would it last longer than the Lead Acid ones I have? Its a LOT lighter.

 

[Deleted member 4366]

The Ebay controller that you linked to above might be OK. It will work, but they don't say what the maximum current is. See if you can find a 15 amp one. I wouldn't go any higher than that because those motors burn out rather easily.

You can use a lithium battery as long as it can provide the current.

 

[OxygenJames]

Thanks Dave (Davey?) - apart from Ebay do you know where else to look - the ebay ones don't seem very good at telling you that level of information.

 

[OxygenJames]

Plus - I notice on the original controller - from the label - it says Max current 30A. Is there a particular reason you are suggesting I get one with a lower rated current?

 

[OxygenJames]

And on the Lithium battery - apart from it being lighter - will it last longer per charge - as in the current lead acid batteries give me around 40 min use - will the lithium ones give me a longer time than that? The LA ones are rated 7 ahr - the lithium 7.5 - is the only real advantage the weight and how many times you can charge it before it dies on you - or will my range improve significantly?

 

[OxygenJames]

Plus..... (sorry)..... if a controller is rated '500W' - and its 24V - then VxA=W means its 20 Amp rated even if it doesn't say so (well 20.83). Yes?