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Battery problem on Electric scooter

5368 Views 3 Replies 2 Participants Last post by  dougingraham
Hey guys i have a quick question about my electric scooter,

so i purchased a razor ecosmart metro 36 volt 21amp electric scooter 2 years ago and the battery used to last me about 5miles but now it only lasts about 1 and a half :( i was wondering how i could increase the range (and hopefully torque and speed:D)

should i replace the batteries with deep cycle batteries or just add a deep cycle battery???

Please make answer as specific as posible,

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Your batteries are shot. If you baby your Lead acid and you are lucky you can get up to 5 years of life with a gradual loss of range. If you don't you can get 2 years with a gradual loss of range. Replace the lead with lithium types of cells. If you do this you will most likely have to replace the charger as well. For a lithium battery of the same weight as the current lead pack you will get somewhere between three and four times the range of the new lead battery and it will last you three or four times longer.

A 36 volt battery will be 12 lithium iron phosphate cells which is what I would suggest as a direct replacement.

The speed and torque may be limited by the motor controller. Speed is related to battery voltage. Increasing the pack voltage might be necessary to increase the top speed. You might not be able to increase the voltage unless the motor controller can handle it. You could also change the effective gearing between the motor and the driven wheel to increase the top speed. This will however reduce the torque. The torque an electric motor puts out is proportional to the motor current. The motor controller is probably limiting this to control heat and prevent the motor from burning up or killing the battery prematurely.

In order to get more speed and torque you might have to replace motor, controller, and batteries. Without knowing exactly what all these parts currently are it is impossible to make specific recommendations.
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Thank you so much i think i will replace the controller and motor as well as buy lipo batteries...... is there anything i can do to help u out by liking your blog or something????
You are welcome.

I don't know that you need to replace those items. You might be able to get away with increasing the battery voltage a little bit. That alone would increase the top speed (assuming the controller allows it). You might also be able to reconfigure the controller to allow for higher current which will increase the torque. Changing everything is probably a little extreme. Unless you know what you are changing you could make things worse than they are now. Adding a bunch of speed might require an upgrade to the brakes. There are always consequences to changes.

I don't have a blog but there is a reputation symbol that looks like a balance above this post on the right. If you are compelled to do something you can click that and add to my reputation.
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