Help with additional lights on a Mobility Scooter.

HI new here so hope this is right place to post.

I have a mobility scooter and the lights are so poor as to be useless and what I consider unsafe. I want to add additional lights but have no idea to how to figure out if they will draw too much power, making them a bad idea.

The mobility scooter runs on 24v provided by 2x 12v 50ah batteries in series thus giving the 24v and under ideal conditions is supposed to have a range of 25 miles. The lights are a pair of LED Pods at 18w so a total of 36w. (I have found lower wattage ones but these seem to be the most popular)

Would the power draw of these be too much for the batteries? Would the power draw significantly reduce the range? Is the whole idea nonsense and I should get bicycle lights

( which I really don't want to do for various reasons)?  Any help would certainly be appreciated. Many Thanks

Another two 18W isn’t going reduce the full charge mileage greatly, possibly a ¼ of a mile if that. You will have a charge monitor on the scooter and I’m sure you keep an eye that as you’d be pushing the scooter home.

Obviously any extra load will reduce range by some amount, as will ageing batteries.

However, as long as you don't use the full range I doubt if you would notice the difference, and I would think the improved safety well worth the loss. 

Just thinking. Have you actually seen your proposed lamps operating?  36 watts of focused LED light sounds quite a lot to me.

Not sure how correct my theoretical calculations are but here is what I was thinking:

If the original spec can do 25miles off a 50ampHour full charged battery that would suggest it is consuming 2ah per mile?      (50ah / 25mile  = 2ah per mile)

Don't know what the average speed is but guessing at 5mph, if it can do 25miles fully charged at 5mph that suggests 5hours of usage?   (25miles / 5mph = 5hours duration)

5 hours to consume 50ah suggests 10amps per hour?    ( 50ah / 5hours = 10amps per hour )

Your proposed lights rated at 36watts (for the pair) will draw 1.5amps.   (36watts / 24volts  = 1.5amps)

So if your lights are switched on for 1 hour, that will take 1.5ah,  which is a bit less than the 2ah per mile.

That implies for every hour your lights are on you will lose about 1 mile of total range.

Or, assuming you have the lights permanently on, every hour you wil use 11.5ah  (10+1.5),

which gives 4hrs 20mins battery life,  at 5mph that's approx. 21.5miles range, if you are out in the dark with lights full on for the whole journey.

That all made sense as I was thinking it though, but I may have missed something obvious? Perhaps some of our other members double check my logic?

Doc H.

My friend’s scooter was supposed to be limited to 8mph, note, supposed to be. I timed it at 11mph, at that speed the battery life and distance was abysmal. They don’t corner that well either, several times I had to drag him out of the A38 and then right the scooter.  The thing to keep an eye on is the charge bar graph.

Tony S said:

My friend’s scooter was supposed to be limited to 8mph, note, supposed to be. I timed it at 11mph, at that speed the battery life and distance was abysmal. They don’t corner that well either, several times I had to drag him out of the A38 and then right the scooter.  The thing to keep an eye on is the charge bar graph.

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There is one I see in town that is very narrow indeed, presumably to get into and around the shops.  The guy drives it around in winter covered in a complete transparent plastic cover.  I am honestly surprised with the winds we get at timed that it has not blown over yet, it looks hideously unstable and unsafe to me.