Longer ride time

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Capataz1624   1 µW

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Longer ride time

Post by Capataz1624 » Jan 12 2021 7:57pm

New to endless I'm in need of some help I currently have a 48v 10ah so I purchase. A. 36 v battery I want to see if there's a way to add it to my 48v so I. Cann get more ah. If someone can please help

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e-beach   1.21 GW

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Re: Longer ride time

Post by e-beach » Jan 12 2021 8:50pm

Well, it would have been better to purchase a duplicate battery to what you have. But since you didn't, you either have to make a 48v battery out of the 36v or a 36v out of the 48v battery. You did not reference your motor or controller but because you stated you have a 48v system originally, then you would need to take apart your 36v battery and make it into a 48v battery. Then you will need to hook it up to your original system when your original battery has hit LVC. Chances your two battery's have dissimilar cell types making it hard if not completely wrong to mix them together.

So your first steps should be to take pictures of what you have (Make sure they are in focus.) and post them.

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amberwolf   100 GW

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Re: Longer ride time

Post by amberwolf » Jan 12 2021 10:31pm

Capataz1624 wrote:
Jan 12 2021 7:57pm
I purchase. A. 36 v battery I want to see if there's a way to add it to my 48v so I. Cann get more ah.
Unfortunately there isn't a way for you to simply add them to each other to get more Ah.

If your controller supports a range of voltages that include both of those, then you can run on your 48v battery until it is empty, then disconnect it, then connect your 36v battery and run on that until it is empty. The 36v battery will only run your bike at about 3/4 of the speed the 48v battery does, though, typically. (depends on the system)

When you're done riding, then you disconnect both of them and recharge them with their respective chargers.

Also, you cannot use the charger from either one on the other, or you will either damage the battery, or the charger, or both, and risk a fire.


If you were to spend enough time learning about batteries to learn all the dangers in it, and how to do it right (and wrong, so you can avoid that), you could disassemble both batteries and build them into one larger-Ah battery. But this is a very advanced thing to do, and has risks including starting a fire you can't put out, if you do something wrong.


Your best bet is to see if the seller you bought the 36v from will take it back and trade you for a 48v like you already have. You need to first make sure that the 48v battery you have is what they call a "13s", because some places call a "14s" battery 48v (though more call it "52v"), and that's not compatible with a 13s version. You must get the *same* version, so you have either two 14s or two 13s 48v batteries, before you can use them at the same time.

If you had two 48v batteries, you could simply parallel their output wires to run them both at the same time.



Another potential option is to get a "Buck/Boost DC-DC" for each battery, and set the output voltage for both to be exactly the same, then parallel both of those outputs together (while the inputs of both DC-DCs go separately to each of their batteries). But the DC-DC's each have to be able to handle the full power (watts) the bike draws at peak and continously, in case one fails or the battery powering it shuts down. This is not as complicated as disassembling both batteries to make one big one, but there is still risk, and it adds cost and complexity to your bike, increasing the chance of something going wrong on a ride leaving you with no power.

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E-HP   1 MW

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Re: Longer ride time

Post by E-HP » Jan 12 2021 11:11pm

Capataz1624 wrote:
Jan 12 2021 7:57pm
New to endless I'm in need of some help I currently have a 48v 10ah so I purchase. A. 36 v battery I want to see if there's a way to add it to my 48v so I. Cann get more ah. If someone can please help
I would return the battery if possible. I'm guessing by your post, that breaking down the battery and reconfiguring it is likely beyond you current knowledge or abilities.

Capataz1624   1 µW

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Re: Longer ride time

Post by Capataz1624 » Jan 12 2021 11:24pm

Thanks for the advice and yes it's beyond my knowledge I'm New to all this ebike and battery watts and volts I'll do some research and see if I'm able to make one mega battery. Thanks onces again :bigthumb:

markz   100 GW

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Re: Longer ride time

Post by markz » Jan 12 2021 11:26pm

Capataz1624 wrote:
Jan 12 2021 11:24pm
Thanks for the advice and yes it's beyond my knowledge I'm New to all this ebike and battery watts and volts I'll do some research and see if I'm able to make one mega battery. Thanks onces again :bigthumb:
There will be more then just "some" reading and research.

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E-HP   1 MW

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Re: Longer ride time

Post by E-HP » Jan 12 2021 11:36pm

Capataz1624 wrote:
Jan 12 2021 11:24pm
Thanks for the advice and yes it's beyond my knowledge I'm New to all this ebike and battery watts and volts I'll do some research and see if I'm able to make one mega battery. Thanks onces again :bigthumb:
Good luck, and remember that these batteries are far from safe; battery fires are a reality.

If both batteries are 10Ah, there's a possibility of running them in series (23S, 85V), and get a controller that can handle that voltage. You'd need to monitor each pack's voltage while riding to make sure they don't drop below 39V and 30V respectively.

http://powervelocity.com/home/54-12f-eb ... e-4kw.html

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amberwolf   100 GW

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Re: Longer ride time

Post by amberwolf » Jan 13 2021 1:51am

Keep in mind if you do series the batteries for higher voltage, the motor will now spin almost twice as fast for the same throttle setting. So you'll need to use about half of the amount of throttle that you used to for the same speed as before.

(you don't want to use a faster speed because that will shorten your ride time, as it takes more power to go faster).

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dogman dan   100 GW

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Re: Longer ride time

Post by dogman dan » Jan 13 2021 7:51am

If your 36v battery won't run your 48v system at all, you do have one last option. Add a 12v battery to it in series, making it a 48v battery. Then just run one battery, then the 36v +12v one. Charge them individually as well.

If your bike will run on 36v, then just run one battery, then the other. I did that for quite a few years, and it works fine.

markz   100 GW

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Re: Longer ride time

Post by markz » Jan 14 2021 6:10am

Another option is to find the lvc voltage divider network within the pcb inside the controller and change out a resistor to lower the lvc.

Optional advice is to buy a DC-DC booster to boost your 36V battery to 48V but you'll lose efficiency in the DCDC.

Buy a 36V controller

Add battery in series

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dogman dan   100 GW

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Re: Longer ride time

Post by dogman dan » Jan 14 2021 7:07am

Buy a controller that works on 36v or 48v will work too. Maybe that's what Markz meant, quite a few 36v systems can also run 48v.

Then you can run one, then the other. I used to run my 48v battery up the mountain till it ran out, then come back down, and across the flats to home on the 36v.

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