ATV Battery Build

[majerus1223]

Building a 2001 Polaris Sportsman with a motor driven off the transmission. I am looking a buying 2 of these 2.2kWh 44.4v Lithium Ion Alfa Romeo Tonale Battery Module cells and connect them in a series connection.

Couple questions regarding this.

Is there a way to calculate if this is enough power to run the motor, controller, vehicle combo?

Do I need to add a parallel cell group?

What BMS should be used? I was thinking an ANT 17s - 24s 500A-400A 420A. Should I look somewhere else? Thought that by buying a larger BMS and turning the power down hopefully wouldnt run into future problems.

Am I missing anything else? This is my first battery build not using something with lead acid batteries.

Controller : ND961800b
Motor: QS180 90H
Endless Sphere Thread: 2001 Polaris Sportsman Conversion

Thanks!

Diagram:

 

[amberwolf]

Building a 2001 Polaris Sportsman with a motor driven off the transmission. I am looking a buying 2 of these 2.2kWh 44.4v Lithium Ion Alfa Romeo Tonale Battery Module cells and connect them in a series connection.

Couple questions regarding this.

Is there a way to calculate if this is enough power to run the motor, controller, vehicle combo?

You can use simulators / calculators like those at ebikes.ca to determine the power required to do the job you want the vehicle to do for you, under your specific riding conditions. Use the worst case conditions and the hardest job you need it to do, to get the highest power draw it will take.

Then you can use that guesstimate to pick a motor and controller that will do that job.

Then you can pick a battery that can supply all that power (w) for the amount of time (wh) you need to use the vehicle.

Do I need to add a parallel cell group?

What do you mean, exactly?

What BMS should be used? I was thinking an ANT 17s - 24s 500A-400A 420A. Should I look somewhere else? Thought that by buying a larger BMS and turning the power down hopefully wouldnt run into future problems.

Probably a good idea. But you have to find out how much power it will take to do the job you need first. When you use a more-capable BMS, be sure to set it's limits to below those of the cells you're using (if you run them at their limits, it can stress them, and do so more the older and less capable they get).

 

[majerus1223]

Basically this, I guess another "module" in parallel.

 

[amberwolf]

I don't know exactly what you're meaning with the drawing or "Basically this, I guess another "module" in parallel."

Your question of "Do I need to add a parallel cell group?" needs more info to answer it. So the best answer I can give is a set of questions you can use to answer it:

What does the system require to do the job you want it to do under your riding conditions? How much power/current? How much capacity?

Does a single set of modules in series provide that?

If not, then adding more modules in parallel until it does provide that would work.


Your drawing doesn't show the required balance/sense connections from the paralleled packs to the BMS. If you don't use those, these packs will not be protected against overcharge or overdischarge or cell damage, as the BMS won't know their cell conditions to trigger shutoff when necessary, unless you are using a separate BMS to handle them.

 

[majerus1223]

I didnt draw the sensor wires but figured they would be there sorry about that.

The battery "modules" each one I was looking to buy is 2.2kWh @ 44V

The original vehicle pack the modules I am looking at I belive can support a 90kW motor based on the original car being an alfa Tonale. (Using wikipedia as a source Alfa Romeo Tonale - Wikipedia )

The pack in the vehicle is 304V , 51Ah, Cells are from CATL, and its NCM type.

Therefore I think one module can output 296 amps? (90,000 / 304V)

The listing on JAG site says 400 however.

Ill run the motor calculator for my QS motor just trying to find the paramater information to populate into the simulator

 

[majerus1223]

Updated diagram

 

[amberwolf]

I didnt draw the sensor wires but figured they would be there sorry about that.

The battery "modules" each one I was looking to buy is 2.2kWh @ 44V

That tells you voltage and capacity, but does not tell you current capability.

The original vehicle pack the modules I am looking at I belive can support a 90kW motor based on the original car being an alfa Tonale. (Using wikipedia as a source Alfa Romeo Tonale - Wikipedia )

The pack in the vehicle is 304V , 51Ah, Cells are from CATL, and its NCM type.

Therefore I think one module can output 296 amps? (90,000 / 304V)

Are the modules used only in series in that vehicle? If so, then yes. If they are paralleled, then divide by however many parallel modules were used.

The listing on JAG site says 400 however.

Does it say how they came up with that? If not, it's safer to go with the lower estimate based on power in the vehicle they came from.

Ill run the motor calculator for my QS motor just trying to find the paramater information to populate into the simulator

It's not terribly important whether you have completely accurate motor info to find out how many watts it will take to do the job. As long as you can get in the ballpark, and can get it to go up the slopes you have at the speed you need, it'll give you a useful power guesstimate. Round up whatever results you get, rather than down, and roudn up in all your calculations; overestimating a need, and underestimating the ability to fill that, will usually work out.

 

[majerus1223]

Are the modules used only in series in that vehicle? If so, then yes. If they are paralleled, then divide by however many parallel modules were used.

Seems like it, calculated this as the pack is 15kWh, the "modules" are 44V and the entire pack is 304V. (304V/44V = 6.9), as well as (each module is 22000Wh * 7 = 15,400Wh) For a total of 7 "modules" in the pack.

Does it say how they came up with that? If not, it's safer to go with the lower estimate based on power in the vehicle they came from.

Great question not sure honestly.

It's not terribly important whether you have completely accurate motor info to find out how many watts it will take to do the job. As long as you can get in the ballpark, and can get it to go up the slopes you have at the speed you need, it'll give you a useful power guesstimate. Round up whatever results you get, rather than down, and roudn up in all your calculations; overestimating a need, and underestimating the ability to fill that, will usually work out.

This part is hard.. Trying to find the specs of the motor I got and understanding of this tool is proving to be a challenge.

I made this "custom mid drive motor"




With these settings..



Still playing with this to try to figure it out.

 

[majerus1223]

Watching the videos on using the tool.. should clear some things up.

 

[amberwolf]

The trip simulator would probably be easier to understand for your purposes

Trip Simulator - Tools

ebikes.ca

You can use the google maps function to draw a trip on a map and if that map's elevation/etc is correct, it'll give you approximately the power required to do what you want.
I don't think it has a gearing function, but if you use the gear ratio to multiply or divide with the motor parameters you have, you can put them in there as if it was just that. (my wording might not make sense; i'm very tired atm)

 

[j bjork]

2 modules in series would probably work fine, but with a little limit in power (Limited to about 400A, maybe 35kw or so) and range. If you can fit 4 modules it would be better, but heavier of course.