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Im looking at the Westart NCM120A battery module to build my battery pack with.
Im trying to calculate some of the values of the pack, But im learning as I go, So im trying to understand.
Perhaps someone could tell me if im going wrong and explain it like im 5.
On the spec sheet for the module the nominal capacity is listed as 120Ah @ 0.3C discharge
A little further down the discharging current is listed as 2C continuous.
On the website of the seller they list the burst discharge as 5C
Does that mean that at 2C, the amps discharged in a continuous situation are approximately 790A?
If the module discharges at 120A at 0.3C, then 120A multiplied by 3.3 (0.99C) would be 396A, then multiplied by 2 (1.98C) equals 792A
If I am correct in my calculation, then 792A draw would be an acceptable discharge current, with a short burst at 5C being 1,980A
Is this calculated correctly? Or am I very wrong in my approach?
If this is right, then at 360v (nominal pack voltage with 100 modules) and 790A, 284kw of power is what the inverter would be putting through the motor, which is basically full power for a Tesla SDU with the inverter never really needing to draw any more than 2C of battery output, Which should give the pack a long and healthy lifespan.
Even at my smallest pack size, (88 modules) the nominal pack voltage would be 317v and 790A, for 250kw of power. Still a very healthy figure and well within the operating specs of the motor.
My other question is, From this, how do I calculate the total kWh of the pack? from that I should be able to work out a rough expected range.
Im trying to calculate some of the values of the pack, But im learning as I go, So im trying to understand.
Perhaps someone could tell me if im going wrong and explain it like im 5.
On the spec sheet for the module the nominal capacity is listed as 120Ah @ 0.3C discharge
A little further down the discharging current is listed as 2C continuous.
On the website of the seller they list the burst discharge as 5C
Does that mean that at 2C, the amps discharged in a continuous situation are approximately 790A?
If the module discharges at 120A at 0.3C, then 120A multiplied by 3.3 (0.99C) would be 396A, then multiplied by 2 (1.98C) equals 792A
If I am correct in my calculation, then 792A draw would be an acceptable discharge current, with a short burst at 5C being 1,980A
Is this calculated correctly? Or am I very wrong in my approach?
If this is right, then at 360v (nominal pack voltage with 100 modules) and 790A, 284kw of power is what the inverter would be putting through the motor, which is basically full power for a Tesla SDU with the inverter never really needing to draw any more than 2C of battery output, Which should give the pack a long and healthy lifespan.
Even at my smallest pack size, (88 modules) the nominal pack voltage would be 317v and 790A, for 250kw of power. Still a very healthy figure and well within the operating specs of the motor.
My other question is, From this, how do I calculate the total kWh of the pack? from that I should be able to work out a rough expected range.
