Voltage gt 500 E-bike E-Scooter

Hi, i picked up a 500 watt 48v 12ah voltage gt 500 ebike/scooter ( has peddles) it does about 36 kmph or about 22 miles per hour top speed tho the company/dealers claim it will do 40kmph , unless i am wrong the online calculator for km to mph means 36kmph is 22 miles per hour. is that right? also, it has 4 12 volt 12 ah batteries which so far i have only gone about 9 miles one way before giving it a 2 hour charge while i was shopping in a flea market. so i have never yet tested to see it will do the advertised 30 miles total on a charge. the skooter is really comfortable and the speed is not boring tho i'd like to quicken it a bit more and certainly insure i can go about 30 miles round trip because i live 12 miles from the beach and want to ride there and back. but the skooters peddles are useless just for show, when the battery dies it's like trying to drag an elephant on the bike. so i have to make sure i have enough juice. ok here are my questions for anybody who has the bike , does it really do 30 miles on a charge? and can i safely ad say a 6 volt 12 ah or more battery in the proper serial or parallel manner and not burn out the controller or motor? I would enjoy hearing from anybody who has this skooter bike. and info on how to speed it up a bit more and extend the range.

thanks
Brian

I dont have the bike but i can tell you range depends on many factors: The way you drive, the stops, the gradient of the palce you drive, the weight you carry, etc.

Normally for more range you need more Ah so paralel, but maybe your controler acepts more Voltage and you could serial one more batery but any way if it is possible you would need another charger and maybe another BMS to charge this new voltage but will give you more speed (but also consume more baterry if you go full speed)

Those are probably SLA batteries, and so you can effectively cut the Ah available in half at the rates used by the scooter. Unless you pedal with it and ride slowly, with no hills or slopes and no stops, I seriously doubt you'll get anythign remotely close to the range advertised. Unfortunately that's a common problem with advertised claims of range; they don't give you the conditions under which they tested that range, if they even did test it.

If you speed it up you'll need bigger and better batteries to get the range you already have, and then even bigger batteries to get more range than that.

As for actually doing the speed up, you should read around the forum on the many bike and scooter threads about doing that--there are a lot of them that give you the general idea, and how to figure out the specifics on your actual vehicle.

i believe they are sla batteries, tho the batteries themselves are blank, nothing written on them, i opened the battery case, the manufacturer posts they are gell type or something, if i change out the batteries what are the best to use beside going to lithium? best for range, i believe the 15ah versions are same dimensions so would go for that, but what type ( besides lithium) and or brand are the best?

Well, if you don't want to use any lithium batteries, then the only better alternatives to lead-acid (gel-cell, SLA, etc) are NiCd and NiMH, neither of which is probably going to help you much because you really can't parallel them for charge or discharge safely, and they don't come in capacities high enough to do what you need to do.

Lead-acid (SLA from here on) takes a certain physical size/weight to do a certain capacity and current-delivery capability and lifetime, so if you have higher Ah batteries taht are the same physical size/weight as smaller Ah batteries, it is probable that the higher Ah batteries either will deliver less of that Ah when used at the same rate (current) as the lesser Ah batteries, or will last less charge/discharge cycles, or will have more voltage sag, or some combination of all three.


So if you aren't willing or able to either use a much more energy-dense chemistry like one of the many lithium types, your only other option is to add more parallel batteries of the same type you already have (though they could be larger size and capacity), in external boxes or mountings on the scooter.

Because lead is heavy and Peukert's law affects it much more strongly than any other common EV chemistry, you will reach a point of diminishing returns somewhere along the line of adding more capacity/range, because it will take so much more power just to acclerate the extra weight that it will no longer be able to deliver any more power than ti takes to do that.

Where exactly that point is you'd have to experiment with, but I'll say from experience that if you can go with some lithium chemistry, that's got sufficient capacity and a high enough c-rate for your application, you'll be a lot happier. Even though the lithium seems like it costs more than the lead, it doesn't really because it'll last longer and it will not take as much of the right lithium Ah to do the same range as lead.