Poor Range on 48 volt Sla

[Nick Horsfield]

I am using a 48volt 800watt motor kit, simple twist throttle- controller- hub motor set up. And have 4x12 volt SLA's wired in series. They are new batteries. I have two problems with it so far.

1.It is frequently blowing or melting the fuses I put in, but at completely random times. The fuses are mini blade. I am currently using 30amp.

2. This worries me the most: I am only getting 2 miles range! Before the batteries become too weak. I can't find any other threads about this online anywhere, so thought I would ask here.

Does anyone have any experience of this. In theory should be getting a 10 mile range at least.
Any thoughts would be greatly appreciated.

 

[Alan Quay]

30 amps through a mini blade fuse is too much, regardless of what size fuse - I have seen the holders melt at 18 amps. Full size blade should be OK.

I wonder what type of SLA's you have. A picture would help. It could be that you have the ones designed for UPS's and other standby applications. This would explain the loss of range. What capacity are they - 12 or 6 ah is common.

If they are 6ah, and you are pulling >30amps out of them, then 2 miles is about right.

 

[Geebee]

What amp hour are the batteries? what is the max amps on the controller?
If you draw high current out of under sized SLA's there range will plummet, the batteries will get damaged and your bike won't be getting it full performance.

 

[Nick Horsfield]

Thanks everyone. I am using these batteries: POWERLINE 12v 12ah



I am afraid I don't know the Max Amp of the controller. Nor do I know how many amps my batteries are actually pushing as my voltmeter thing is not working. I was refering to the ampage of the fuse when I said 30amp.

So I thought about using a bigger fuse also. Maybe a "Midi" fuse would be better?

 

[trex]

One of the batteries may have become totaslly discharged after 2 miles, having been more discharged than the rest.
when you wire the batteries in series, you need to balance their charge to bring all the batteries to the same state of charge. The simplest way is to discharge the batteries to the same voltage, about 12V then link them back together.