First build electric golf trolley battery advice please

[22huskys]

Hi everyone just asking for some battery advice on my first electric conversion build - my golf trolley which weighs about 20kg with clubs. I have managed to get a 300w 36v 6.5 inch motor hub wheel of a hoverboard for cheap which im going to swap with the wheel on the front of my golf trolley. I have a speed controller and throttle on the way but i just dont know what battery would be best to use or size i would need for a 4hr plus round granted it wont be switched on going downhill or flat.

I have some makita nimh 18v batteries i was thinking of using with a holder mount and just swapping batteries out as or if i need to during round from my bag they can easily be charged with their charger after. How long would one of them batteries realistically last? I was looking at buying new lipo batteries but the extra safety and charging equipment needed around them puts me off. Lead acid is too heavy inefficient and big. Ive very little mounting room. Was considering buying new lion drill batteries but id need the charger aswell which would be expensive. Does anyone have any suggestions? Thank you

 

[amberwolf]

You'd need to know how much power the system will use to know how long the batteries will last.

Some stuff to help figure that out:

How fast did the hoverboard go, that the motor came from, at full speed?

How fast do you need the trolley to go?

How long do you need it to move at any one time?

Since most of it's usage on hills, how steep are the hills and how long?


Basically, the less speed you need out of it, the less power it will take. (and the closer you go to it's designed usage speed, the more efficient it will probably be)

The shorter time it needs to move, the less power.

The flatter the terrain, the less power.



Educated guess: Since I doubt you're running it more than a tenth the time you're there, and I would guess you're only going to use a few dozen watts most of that time, you probably don't need more than a hundred watthours, probably less.

At 36v, 100wh would be 100Wh / 36V = 2.78Ah.

So if those Makita batteries are about 21v full each, then you could put two in series, and run it off of that. (A "36v" controller expects it's battery to be about 42v full, and about 30-32v empty.) Whenever they get low just swap both out for another pair, and so on.

 

[22huskys]

Thanks. I will try 2 of the makita batteries in series and see how that goes. I already have the batteries anyway and theyd be easy to mount. Its hard to get exact figures since the terrain is so different so trial and error is probably best. It would only need to go walking pace about 5mph. It takes about 5 minutes maybe to walk a hole and there about 6 hilly ones so it would probably only be on for 30 mins max for that. Hills maybe 5 to 10 percent incline. Im not sure how fast the hoverboard went was just the wheel i bought but similar e scooter builds on youtube appear to go 15 to 20mph with the same sort of wheel.

 

[amberwolf]

Then I would guess it probably will only take a couple Ah to do the distance you're after, if that.