What is the lowest battery ah I can have with 750w Bafang mid drive ?

Electrically assisted bikes, trikes, etc.
Del15476
Posts: 9
Joined: 5 Sep 2018, 9:01pm

What is the lowest battery ah I can have with 750w Bafang mid drive ?

Postby Del15476 » 10 Sep 2018, 5:44am

“””Hailong 48V 10Hailong 48V 10Ah Battery PackAh Battery Pack“”
Hi I know I need a bigger battery for the 750w mid drive. But does anyone know if this @Hailong 48V 10Ah Battery”” will work ? Thanks

hemo
Posts: 294
Joined: 16 Nov 2017, 5:40pm
Location: West Sussex

Re: What is the lowest battery ah I can have with 750w Bafang mid drive ?

Postby hemo » 10 Sep 2018, 2:55pm

You need to supply a link so we can see the battery and the full specs.
Cells used will be 2500mah capacity and 13s 4p configuration to give 48v 10ah/480wh.
The real detail needed is the actual cells used inside, make and specific name of cell used.


750W BBS is a high performance mid drive and needs a high performance battery to excel.
The 750w BBS can output 1200w so you need a battery with specs that can comfortably handle 1200w output and not one that can just cope it, this means one with very good 10a + rated cells inside rather then mediocre cells of 5 -8a.
With the 750w BBS it has potential 25a load/draw, you need a battery that can out put more then 25a with a higher limit. A 48v 10ah battery is 480wh if hooning about in top assist you will maybe get 20 miles range if the battery is a decent one with v.good cells.
48v battery should have a minimum 40a output and 10a + rated cells to deliver the power better. The better the cell used then the better performance it can sustain without being stressed, cells that are stressed less have a better life span and voltage performance is higher up the throughout the voltage range when a high amp load is asked of it.
Batteries with poor/mediocre cells will not last as long and will show up their poorer performance by cutting out power as the voltage decreases when used under high amp load esp on hills or in full assist level, this is known as voltage sag and recovers when the amp load is lessened.
Cells used is also dependant on whether 52 (4 parallel) or 65 (5 parallel) are used.

Good cells to look out for are.
Samsung 30Q 15a rated cells ( 52 cells inside) as a 13s 4p configuration capable of 60 - 80 amp supply.
Panasonic GA 10a rated but can handle 12a and supply 40/48a in 4P config.
Panasonic PF 10A.
LG MJ1 10a.

Also cell capacity needs to be taken in to account, the more mah a cell has more range the battery as a whole will have. All will depend on how much rnage you want to suit your purposes.

hemo
Posts: 294
Joined: 16 Nov 2017, 5:40pm
Location: West Sussex

Re: What is the lowest battery ah I can have with 750w Bafang mid drive ?

Postby hemo » 10 Sep 2018, 3:10pm

As regard to your main question depends on how far and terrain you want to ride.

The lowest ah you could run with would be 5ah - 7ah with v.good 15 or 20a rated cells but distance would be hampered most likely about 10 -12 miles, this would be a bespoke 26 cell battery would work instead of the more common 52 or 65 cell batteries.

Marc
Posts: 48
Joined: 18 Aug 2016, 6:03pm
Location: Hamburg, Germany
Contact:

Re: What is the lowest battery ah I can have with 750w Bafang mid drive ?

Postby Marc » 14 Sep 2018, 5:03am

@Del15476: Stop right there! The most important part of any EV (especially ebikes) is its battery.
If you are strapped for cash to buy a good battery, save more money and take the time to learn more about the topic.

As a rule of thump, get a battery with high quality battery cells and enough capacity to provide twice the range you actually need (especially if you are commuting). Don't forget: The capacity of a battery will decrease with time. High capacity cells will age a bit faster than cells designed for high power output.

https://em3ev.com/store for instance, is a vendor with very good reputation, reasonable prices and they build high quality batteries.
Paul is a Brit located in Hong Kong (or thereabouts).

Del15476
Posts: 9
Joined: 5 Sep 2018, 9:01pm

Re: What is the lowest battery ah I can have with 750w Bafang mid drive ?

Postby Del15476 » 14 Sep 2018, 8:11pm

Cheers
hemo wrote:As regard to your main question depends on how far and terrain you want to ride.

The lowest ah you could run with would be 5ah - 7ah with v.good 15 or 20a rated cells but distance would be hampered most likely about 10 -12 miles, this would be a bespoke 26 cell battery would work instead of the more common 52 or 65 cell batteries.