EM3ev 52V battery choices opinion

[butters149]

Hi everyone,

I've decided to pull the trigger on a leafbike hub motor. Below are the specs. I am down to two types of battery choices that EM3EV offers, both 52V. Ultimately I am after more performance than range, but I would also consider a battery that has more AH (range) if the performance isnt much of a difference. Below are my three choices, which one is best?

1.) EM3ev 52V (14S5P) Jumbo Shark Ebike Battery - 52V - 17Ah - Samsung 3E cells
2.) EM3ev 52V (14S4P) Super Shark Ebike Battery - 52 V - 11.8Ah - Samsung 30Q cells
3.) EM3ev 52V (14S4P) Super Shark Ebike Battery - 52 V - 11.8Ah - LG HG2 cells

Motor Specs:
Voltage: 48V
>>. Power: 2000W
>>. Efficiency: 90.5%
>>. Max speed: 68.9 kmh -- 42.7 mph Default (Optional other speed: 35mph or 25mph,15mph...)

Controller Specs
>. Driver: brushless controller
>>. MOSFET: 24 PCS
>>. With LCD: YES
>>. Rated Voltage: DC 48 Volts
>>. Min. Voltage: DC 40 ± 0.5 V
>>. Rated power: 2000 Watts
>>. Casing material: aluminium
>>. Maximum Current: 55 A ± 1 Amps
>>. Thermal: aluminum shell and the substrate
>>. 3 phase 120° brushless motor
>>. Operating Conditions: -20~45 °C

 

[pwd]

What is your reason for the step down from 14S5P of Samsung 35Es to 14S4P of the other cells? Why not go with 14S5P of the others?

 

[markz]

That is what you have to pay attention to because you do not want to stress the battery, the higher the Ah capacity the lower the discharge (A).

30Q is 15A Maximum Continuous, so 11.8Ah is 4P so your max discharge is 15x4=60A this is your second best bet!
LG H2 is 20A and is 3Ah per can, so 3Ah x 4 = 12Ah which is your 11.8Ah, so 20Ax4=80A this is your best bet!
I assume thats 35E so 35E is 8A per parellel string, they are 3.5Ah x 5 = 17.5Ahw which is your 17Ah, so 8Ax5=45A which is 10A short of your 55A discharge.

Ideally you want a higher Ah capacity to get more discharge current so you do not stress the battery. Like everything it is a balance between physical size of battery pack, cost, capacity (Ah) and discharge, along with your range, how often you want to charge.

1.) EM3ev 52V (14S5P) Jumbo Shark Ebike Battery - 52V - 17Ah - Samsung 3E cells
2.) EM3ev 52V (14S4P) Super Shark Ebike Battery - 52 V - 11.8Ah - Samsung 30Q cells
3.) EM3ev 52V (14S4P) Super Shark Ebike Battery - 52 V - 11.8Ah - LG HG2 cells

Maximum Current: 55 A ± 1 Amps

 

[butters149]

What is your reason for the step down from 14S5P of Samsung 35Es to 14S4P of the other cells? Why not go with 14S5P of the others?

Because they don't offer other cells in the 5P 17ah configuration.

 

[butters149]

That is what you have to pay attention to because you do not want to stress the battery, the higher the Ah capacity the lower the discharge (A).

30Q is 15A Maximum Continuous, so 11.8Ah is 4P so your max discharge is 15x4=60A this is your second best bet!
LG H2 is 20A and is 3Ah per can, so 3Ah x 4 = 12Ah which is your 11.8Ah, so 20Ax4=80A this is your best bet!
I assume thats 35E so 35E is 8A per parellel string, they are 3.5Ah x 5 = 17.5Ahw which is your 17Ah, so 8Ax5=45A which is 10A short of your 55A discharge.

Ideally you want a higher Ah capacity to get more discharge current so you do not stress the battery. Like everything it is a balance between physical size of battery pack, cost, capacity (Ah) and discharge, along with your range, how often you want to charge.

1.) EM3ev 52V (14S5P) Jumbo Shark Ebike Battery - 52V - 17Ah - Samsung 3E cells
2.) EM3ev 52V (14S4P) Super Shark Ebike Battery - 52 V - 11.8Ah - Samsung 30Q cells
3.) EM3ev 52V (14S4P) Super Shark Ebike Battery - 52 V - 11.8Ah - LG HG2 cells

Maximum Current: 55 A ± 1 Amps

So I should go with option 1? I am confused and did so much research this week lol.

 

[pwd]

You should fully understand what you are buying before you make your purchase. Markz has layed out some good info. I recommend giving this a full read to help clear up any confusion about battery packs and their specifications etc..:

https://endless-sphere.com/forums/viewtopic.php?f=14&t=26621

 

[markz]

So I should go with option 1? I am confused and did so much research this week lol.

It is like this, you want V8 power from a 4 cylinder vehicle. Meaning your discharge amps from battery that your controller pulls when you twist the throttle, strains you battery. The battery is the most expensive and #1 component of your e-ride. Main key points for the battery cells/pack brand and model. Is the Discharge in (Amps - [A]) and your controllers amp rating, in your case your controllers amp rating is 55A. When you twist the throttle, is will sooner or later ask for 55A from your battery. If your battery pack maximum output current rating is 25A, you will fry your battery if you do not have a BMS.

When you see things like 14S9P for any model brand, you take the nominal voltage, 3.70V for Li-Ion times 14S 51.8V and the marketer states 52V. 9P is your Ah, or range. Take same model and brand of battery, take its Ah whether its 2.5Ah or 3Ah and times it by 9, so 3Ah x 9 = 27Ah, next is the discharge for the same model brand of battery. 20A times by 9P is 180A, your controller is 55A max output, that is ideal. You do not want 40A max from battery for 55A controller. Again V8 power from a 4cyl = bad news!
If they state 25R, then its 2.5Ah, 3.7V 20A.


With EM3EV, they will have a BMS (Battery Management System) so you will get a lot of BMS cut outs, big pain.
LG HG2 is your first choice.
30Q is your second choice.

By LG HG2!
But if you can buy a higher Ah pack in LG HG2.

Other options are
https://em3ev.com/shop/50v-14s9p-large-triangle-pack/
the 25R is a great battery pack, it is 22.05Ah pack at 20A, and 14S9P, so 180A and

Another in 25R or 35E
https://em3ev.com/shop/em3ev-72v-20s10p-rectangle-battery-pack-24-5ah-29-5ah/

but if those are too expensive, LG HG2 is good too!

 

[butters149]

So I should go with option 1? I am confused and did so much research this week lol.

It is like this, you want V8 power from a 4 cylinder vehicle. Meaning your discharge amps from battery that your controller pulls when you twist the throttle, strains you battery. The battery is the most expensive and #1 component of your e-ride. Main key points for the battery cells/pack brand and model. Is the Discharge in (Amps - [A]) and your controllers amp rating, in your case your controllers amp rating is 55A. When you twist the throttle, is will sooner or later ask for 55A from your battery. If your battery pack maximum output current rating is 25A, you will fry your battery if you do not have a BMS.

With EM3EV, they will have a BMS (Battery Management System) so you will get a lot of BMS cut outs, big pain.
LG HG2 is your first choice.
30Q is your second choice.

By LG HG2!
But if you can buy a higher Ah pack in LG HG2.

Other options are
https://em3ev.com/shop/50v-14s9p-large-triangle-pack/
the 25R is a great battery pack, it is 22.05Ah pack at 20A, and 14S9P, so 180A and

Another in 25R or 35E
https://em3ev.com/shop/em3ev-72v-20s10p-rectangle-battery-pack-24-5ah-29-5ah/

but if those are too expensive, LG HG2 is good too!

I was close! Your analogy with cars makes much more sense to me since I am a car guy. Thank-you!

 

[markz]

I knew it :lol:

Your analogy with cars makes much more sense to me since I am a car guy. Thank-you!

 

[markz]

I would personally buy a 25R pack in a triangle format, with atleast 4P. The more P or parellel strings the larger the battery, and space is a concern, always is on a bicycle.

Also buy the EM3EV triangle bag!

The LG HG2 is good too.

 

[butters149]

My commutes are usually 4-5 miles. Sometimes I go on group rides which can be longer. I will buy the 14.8 battery with LG2 cells.