Battery questions

[ktoft]

Hi all

I am going to build a battery for my: 48v 1000W front wheel electric bike conversion kit

at first I was sure that i wanted to build a battery with 2600mah and solution 1 but, i read alot of good things about the 52V but I am unsure of which of the two solutions I am listing below would be best? more AH but 48V or less AH but 52V

1) solution: 48V 13s5p = 65pcs which give a 13AH battery

2) solution: 52V 14s4s = 56pcs which gives a 10,4AH battery


BMS:

regarding the BMS what dos: "BMS-for-electric-bike-lithium-battery-with-30A-continuous" mean? other BMS says 40A or 10A what should i choose for the samples above?

48V BMS: https://www.aliexpress.com/item/High...1-3f2264197499

52v BMS: https://www.aliexpress.com/item/Bran...8-718ec6fea51c


Charger:

which is better? and can nr 2 charge more that 13s?

https://www.aliexpress.com/item/48V-...a-cfc7ec143cfc

or

https://www.aliexpress.com/item/29-4...a-cfc7ec143cfc

hope you will take the time and help me out

Thanks

/Kevin

[max_volt]

Those are great questions and generally speaking amps give torque and volts give speed.

[JPLabs]

Right. Build a higher voltage system for better top speed. Build for lower voltage, higher peak current for better max torque. Cells, BMS, and controller.

For a given speed & power operating condition: higher voltage and thus higher motor RPM, with correspondingly lower current, will tend to be more efficient. That's because resistive losses grow with the square of the current. Gearing is different between these alternatives.

The most important difference between your options, though, is the cell count. 65 cells will hold more energy than 56 cells, no matter how you configure them. Between those options, I'd pick #1 simply for the larger pack capacity.

[Criticalthinky]

NEED TO HIRE SOMEONE TO BUILD MY DAD A BATTERY HES AFFECTED FROM THE POWER OUTAGES FOR WILDFIRES. Contact me at Ryanshidyak@gmail.com

[HIGHVOLTAGE]

Try the Endless Sphere Facebook group, they have lots of members who do custom battery requests.

[DaHose]

Hmmmm...... So if there's a choice between two batteries of equal ah, we would always want to go with the higher voltage, provided our controller can handle that higher voltage. Running a rough calculation, 2000W at 48V would pull 41.6A, and 72V would pull 27.8. That's a huge comparative difference in current, and resultant battery life, yes?

[Fred]

Hmmmm...... So if there's a choice between two batteries of equal ah, we would always want to go with the higher voltage, provided our controller can handle that higher voltage. Running a rough calculation, 2000W at 48V would pull 41.6A, and 72V would pull 27.8. That's a huge comparative difference in current, and resultant battery life, yes?

Yes, but it is the amps drawn per cell that counts

1. For the same Ah at 72V, you would use 50% more cells.
2. If you took those 50% more cells and added additional parallel strings to the 48V pack you would also reduce the amps drawn per cell to roughly the same as the 72V pack.

[DaHose]

Ok then. Looking at options, there are some pretty value priced batteries out there. I can find 48V 10ah (13s4p), rated 90A surge, 30A continuous, for about $100, and , 36V 10ah, 60 A surge, 20A continuous (10s4p) for about $75. Both are supposed to be true 18650 packs.

Thinking about what was stated earlier, a pair of 48V batteries in parallel should be a better value than going with the 36V in series (for 72V) thanks to the higher cell count. You also get enough cumulative amperage on the two 48V batteries to power at a full 3000W when the battery is full.

My project is centered around an older Canondale I will ride on single tracks and downhill, so speed is not what I need. I need torque to help with pushing my 250 lb. self up a hill. Looks like a pair of 48V batteries in parallel even gives me options. I can run on a single pack at a full 1000W around town, and use dual packs for max. torque when I go run around the hills chasing skinny little speed monkeys who ride all the time.

Jose

[lmx1111]

I am currently using the unitpackpower battery, it is safe and reliable, and the price is good I recommend it!
Meanwhile, if you want an electric bike or an electric scooter, I highly recommend shengmilobikes and xtron.

[Larisabrownb]

60% of the battery is made up of a combination of materials like zinc (anode), manganese (cathode) and potassium. These materials are all earth elements.A battery is a device that stores chemical energy and converts it to electrical energy. The chemical reactions in a battery involve lovelanguagetest.org the flow of electrons from one material (electrode) to another, through an external circuit. The flow of electrons provides an electric current that can be used to do work.Historically, the word "battery" was used to describe a "series of similar objects grouped together to perform a function," as in a battery of artillery. In 1749, Benjamin Franklin first used the term to describe a series of capacitors he had linked together for his electricity experiments.

[stts]

waste of time