What is the amp pull during the max acceleration in EV mode, when the HSI is maxing out the ECO area? The battery is listed as 36HP, but I suspect during this max acceleration it puts out more than 36HP, even just for a short period of time. Does anyone know for sure?
The system limits battery current to protect the batteries. This means the maximum is a lot less than you'd imagine.
36 HP is the instantaneous max power can be drawn from the battery. 36 HP x 746W/HP = 26856W 26856W / 201V = 133.6 A which is 133.6/ 6.5 = 20.6 or 20.6C of the rated C of the cells.
Yes, a very heavy draw. It wouldn't allow it for more than a few seconds to protect the batteries. They are 6.5 A-Hr cells. If you purchased a 6.5 A-Hr NiMH cell you would find the max. current specified around 50 Amps. The Prius cells are a little special, with better heat dissipation, mostly due to their "prismatic" construction (rectangular vs cylindrical cells). They also have much better inter-cell connection devices, allowing less heating and more current. At any rate, heat is the enemy, and the Prius battery WILL heat up, especially at 100 Amps. You can test this by switching to "EV" mode and see it switch out to normal mode as soon as you get the current up (harder acceleration). It doesn't take much to cause it to switch. 36 HP isn't much when accelerating. As I keep telling people, the Prius is NOT an electric car, it's an electrically assisted gasoline powered car, even in the PIP garb.
The Prius 7.2V module is rated as 1300W/kg. NP2 battery module (in Japanese) So, the peak is 188 A. Anyway, JP PiP sales staff manual says the threshold battery power at the ICE kicking in is 38 kW on the PiP and 21 kW (EV switch on) on the liftback. So, the max amp is approx 104 A on the Gen3 Prius when EV switch is engaged. Ken@Japan
I've seen mine at somewhere around 100-110 A, when going up a steep hill with a full battery. It was a little ways into the PWR bar. Most of the time, I don't think it'll go that high.
I get a reading of just over 30 amps using the ScanGauge BTA (battery amps) when accelerating up to the mid-point of the HSI, just before the ICE kicks in. Is that what you mean? I've not experimented with trying to find out the factors or dependencies that affect this reading.
In "EV" mode under max acceleration when the HSI bar is all the way to the right, I've seen momentary ~100A. In normal mode when accelerating to get on the fwy Iv'e seen 150A.
That was EV mode. Trying to burn off SoC from one long downhill while I was on a short uphill, before getting to another long downhill.
I watched it today with a parallel 8ah lithium pack. 126amps up a hill EV mode. I'll see if torque can record it.
They also have much better inter-cell connection devices, allowing less heating and more current. At any rate, heat is the enemy, and the Prius battery WILL heat up, especially at 100 Amps. NOT FROM MY TESTING and daily use. I have a thermistor installed in each of the temperature wells of my 20 module prius insight conversion, I test in the mountains over several years Never have I seen ANY heat up from CLIMBING the mountain, only from DESCENDING The prius nimh is EXOTHERMIC on charge and ENDOTHERMIC on discharge. An exothermic process releases heat, causing the temperature of the immediate surroundings to rise. An endothermic process absorbs heat and cools the surroundings.” Best was to cool nimh is to LOAD it up and DRAIN it.
