Help Overvolting

Escooter12

1 µW
Joined
Feb 4, 2022
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4
Opened up my controller it’s a 48v scooter. Wondering if I can use a 60v battery. Most of the capacitors seem to be either

Slf 288h
Cd263

But there are two clearly marked 50v
And one marked 25v

I know my scooter charges to 55.1 according to my throttle so something seems off. Can anyone tell me what exactly I should be looking for. Thank you.
 

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Common capacitors in the voltage range you're discussing are rated 63V. So, enough for 48V nominal of LiFePO4 or 52V nominal of Li-ion. But not more than that.
 
So I’ve done a little more research there is one capacitor in the corner rated at 100 volts I found some transistors are 100 volts. The mofsets are 72v.

I’m still trying to decipher the larger capacitors it seems they are also 100 volts. I found this spec sheet from the manufacturer slf. But I’m finding it hard to understand and read is that a range they operate in or range of capacitors they make in that style? The largest capacitor is labeled 80 μF capacitance can I figure out the voltage from that?
 

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Farads are not a measure of voltage.

If all the relevant parts of your circuit are good for 72V, then that should be adequate to tolerate 67.2V (16S fully charged voltage) plus normal transient voltage fluctuations. What battery are you using and what battery are you swapping to?

If you're wrong, well... generic Chinese controllers are cheap. Way cheaper than 60V batteries, anyway.
 
Be careful of two things if you're over volting your system. 1) the controller may have have a low voltage cut-off set for a 48v lithium battery pack (approximately 42v) which is way too low for a 60v pack. 2) even though the components of the controller may have adequate voltage ratings, some may not have the necessary current rating. In other words, using a higher voltage might cause higher current draws too. I can tell you that the PC board traces for the output side of the MOSFETs are not meant to carry a lot of current. You can fix that by soldering 14-12 AWG bare copper wire or braid to the traces to beef them up.

I over volted a lead acid, 36v, 500w escooter one time with a 48v lithium battery pack (beefed up the PC board traces) and measured power draws as high as 1200w under full load. Poor little controller lasted about a year before it finally blew up. Several capacitors that had too low of a voltage rating blew their guts out and a couple of the output MOSFETs blew up. Probably would have lasted longer if I didn't live in San Francisco. Lol.
 
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