First Time EV Buyers: Battery Size and Charging Apprehensions


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Feb 28, 2021
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Chevy Avalanche, BMWs-X3,330cic,K1200RS bike
"It is in an independent system (like Tesla's) that the car adds in friction brakes on top of 100% regen" .
The friction brake in my Tesla adds braking on top of the regen. Period. This is not debatable. It is as plain as the fact that the car has 4 wheels. It is the way things are whether it fits your theory or not.
Show me where I said that friction brakes are NOT added on top of regen? I never stated that, and to the contrary, I provided Bosch documentation to support my claim that they are INTEGRATED - MEANING THEY WORK TOGETHER in the RIvian. That's my whole point - INTEGRATED!

IN THE RIVIAN regen and friction are not an "independent system" as you continue to claim. You keep bringing up Tesla "seat time" watching a display as your only evidence that it must be an "independent system like Tesla's" in the Rivian. Really? Despite the fact that Rivian has stated they use the Bosch integrated system.... Really?

Yes. If the power returned to the battery is unchanged when the friction brake is applied clearly the friction brake has no influence over the regen.

When it shows that the status of the regen is not influenced by the position of or pressure on the brake pedal it tells you they are not coupled. Your bio says you are engineer. You should be able to understand that.
Because I am an engineer, I understand that you don't know how much you don't know, lol. Your observation comments prove that they are integrated, or coupled as you say, not independent.

In a blended regen braking system, when braking, the drive wheels operate at 100% regen under normal braking, to maximize regen. When regen is at maximum, the undriven wheels (or rear axle in a 3 or 4 motor system) receive *just enough additional* friction braking, if needed, to slow the vehicle relative to pedal pressure. What manages that BLENDING to maximize regen? It's the INTEGRATED (not independent) braking system. THAT'S why you don't see a decrease in regen when you use the friction brake. The friction brake will have an influence on regen, unless it is being software controlled to minimize it's influence and maximize regen at all times.

If they were independent as you claim, you would see a drop in regen when you press the friction brake. I'm not going to argue this any further, you can convince these industry experts that you know better than they do by simply watching your Tesla display.

Your problem is that you are assuming that Bosch makes Tesla's braking system. It doesn't. The system described in the video and on the website bears no resemblance to the braking system in my car.
I'm assuming Bosch makes the Tesla system because that's what an industry article claims. I find nothing to disprove that, can you? It makes perfect sense that the Telsa unit would not look like the example on Bosch's web site. Do you expect that physically identical Bosch brake control units would be used in a 3,000 lb BMW i3, a 5,000 lb Model X with ~5,000 towing capacity, and an 8,000 lb Rivian with ~7,500 lbs towing capacity? Of course they are going to be and look different.

I think you confusion may stem from the statements in the iBoost video that it sends signals to the motor. That doesn't mean the traction motor. It means the motor that pressurizes the master cyclinder.
Nope, no confusion here whatsover. It's the opposite - the braking system receives data from the powertrain system to manage the integrated braking process.

My only concern there is that you are misinforming people - not, i suppose, that it matters much in the grand scheme of things/
You're the one misinforming people by your claims that friction and regen braking are independent systems in the Rivian.

I'm exiting this thread, cheers.