battery question?
08-02-20, 03:03 AM
#1
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battery question?
the stock battery oh my bike is 36v 12.5 ah (18650 batteries)... i would like to have another external battery 36v 19.2ah (21700) for longer range..
i will not connect the 2 batteries in parallel... i will use them 1 at a time....
will there be a problem even 1 is 18650 and the other one is 21700?
thanks a lot.... ( new to e-bikes)
i will not connect the 2 batteries in parallel... i will use them 1 at a time....
will there be a problem even 1 is 18650 and the other one is 21700?
thanks a lot.... ( new to e-bikes)
08-02-20, 06:21 AM
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is this right? just connect 1 battery at a time... will a long cable( about 3 feet) from controller to battery 2 be a problem... i like to put my battery 2 to the bikes rear rack...
Last edited by rmnrapido; 08-02-20 at 06:36 AM. Reason: add
08-03-20, 02:01 AM
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the stock battery oh my bike is 36v 12.5 ah (18650 batteries)... i would like to have another external battery 36v 19.2ah (21700) for longer range..
i will not connect the 2 batteries in parallel... i will use them 1 at a time....
will there be a problem even 1 is 18650 and the other one is 21700?
thanks a lot.... ( new to e-bikes)
i will not connect the 2 batteries in parallel... i will use them 1 at a time....
will there be a problem even 1 is 18650 and the other one is 21700?
thanks a lot.... ( new to e-bikes)
Functionality there should be no problem, the higher AmpHour battery should also deliver higher current normally to the controller. Keep the wires similar to those in bike now. Maybe 12 awg or similar and use could quality silicone covered wires.
You might find your computer doesn't report battery properly, hopefully you can access the setting for battery setup, if not the bigger battery may not report what you expect. Just keep track of the numbers. It could be fun to compare the 2 packs on the same trips.
08-03-20, 02:31 AM
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Hai
Functionality there should be no problem, the higher AmpHour battery should also deliver higher current normally to the controller. Keep the wires similar to those in bike now. Maybe 12 awg or similar and use could quality silicone covered wires.
You might find your computer doesn't report battery properly, hopefully you can access the setting for battery setup, if not the bigger battery may not report what you expect. Just keep track of the numbers. It could be fun to compare the 2 packs on the same trips.
Functionality there should be no problem, the higher AmpHour battery should also deliver higher current normally to the controller. Keep the wires similar to those in bike now. Maybe 12 awg or similar and use could quality silicone covered wires.
You might find your computer doesn't report battery properly, hopefully you can access the setting for battery setup, if not the bigger battery may not report what you expect. Just keep track of the numbers. It could be fun to compare the 2 packs on the same trips.
thanks a lot sir....
08-05-20, 03:27 PM
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The controller only sees the voltage and the current, so no problem there.
I would (and do) use a "xt90 connector anti spark" connector to make it easy to swap batteries without any problems caused by sparks when swapping batteries.
I would (and do) use a "xt90 connector anti spark" connector to make it easy to swap batteries without any problems caused by sparks when swapping batteries.
09-08-20, 09:20 AM
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If your motor draws a lot of current, longer wires will drop some voltage and waste energy in the form of heat. You get around that by using the heaviest gauge wire that you;re comfortable with. Wire with silicone insulation with silicone insulation is very flexible, and less likely to fail because of vibration, 12G or 14G should work for 3 feet, That 12G is harder to solder.
Always insukate your XT terminals. I just wired one up the other day and couldn't find my heat shrink or my liquid rubber. Figured there's no harm in using it to charge the battery and I could cover it up later, Well, I passed it thru a battery bag with a metal grommet, and you know what happenned. The bare terminals caught on the ring and kaboom, melted it.
And always double check your polarity too.
Always insukate your XT terminals. I just wired one up the other day and couldn't find my heat shrink or my liquid rubber. Figured there's no harm in using it to charge the battery and I could cover it up later, Well, I passed it thru a battery bag with a metal grommet, and you know what happenned. The bare terminals caught on the ring and kaboom, melted it.
And always double check your polarity too.
Last edited by Doc_Wui; 09-08-20 at 09:23 AM.
09-08-20, 11:32 AM
#12
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Make sure that it is PHYSICALLY impossible to connect both batteries at the same time. Accidentally connecting the batteries parallel at different charge states is highly likely to start a serious fire. If the motor has a single battery lead, that's fine.
