The rather conservative/disappointing range of TMC's first two "real" BEVs left brand enthusiasts with mixed emotions. It is generally accepted that their range estimates are inadequate for a dedicated platform EV launched in 2022 and are only comparable to competitors from 2018-2019 time period (so-called ICEV conversions).
It is well known in the EV industry that increasing range targets creates a death spiral. This is because more range requires more battery, but energy efficiency goes down because the car has to carry extra weight. At some point diminishing returns will make a very long range EV physically overweight and economically overpriced. The 'sweet spot' before diminishing returns start to hurt is dependent on two variables: system energy density (kWh/kg) and system cost ($/kWh). Both are predominantly affected by battery technology.
So how does battery sizing change with range for different segments in 2022? I've made the tables below. I'm using similar set of analysis used in beginning stages of EV design when a range target is chosen based on the battery they have access to and size of the product. The assumptions are very simplistic: the product is baseline single-trim and single-motor configuration since that's the model used for range marketing. The scaling equations are modified each year to fit the most advanced product of that time. The range estimate is based on EPA cycle. Energy is usable capacity so actual capacity is ~10% higher.
For a Segment B city car, there is no clear sweet spot. This is because they are generally very light and efficient to begin with. But they are constrained by volume not weight. The sweet spot today is ~300km range with a ~40kWh battery weighing 1200kg.
For a compact car, the sweet spot seems to be around 400-450km with 62-72kWh battery weighing 1600-1700kg.
For a mid-size SUV, the sweet spot is 400-450km with 75-90kWh battery weighing 2000-2100kg. These are the specs bZ4X/RZ450e should have aimed for if they wanted to be competitive. And indeed we see majority of their competitors in this range.
For a full-size SUV it's hard to say because they are already too heavy and already suffer heavily from diminished return. I would say it's 450-500km with 110-125kWh battery weighing 2600-2800kg.
And pickup trucks are just stupid. With current technology there is no way to build an EV truck with reasonable weight and cost. That's how we got inefficient monsters like Rivian R1T and outright garbage like Hummer EV. A 300-mi truck needs a 130kWh battery and weighs 3 tons!
It is well known in the EV industry that increasing range targets creates a death spiral. This is because more range requires more battery, but energy efficiency goes down because the car has to carry extra weight. At some point diminishing returns will make a very long range EV physically overweight and economically overpriced. The 'sweet spot' before diminishing returns start to hurt is dependent on two variables: system energy density (kWh/kg) and system cost ($/kWh). Both are predominantly affected by battery technology.
So how does battery sizing change with range for different segments in 2022? I've made the tables below. I'm using similar set of analysis used in beginning stages of EV design when a range target is chosen based on the battery they have access to and size of the product. The assumptions are very simplistic: the product is baseline single-trim and single-motor configuration since that's the model used for range marketing. The scaling equations are modified each year to fit the most advanced product of that time. The range estimate is based on EPA cycle. Energy is usable capacity so actual capacity is ~10% higher.
For a Segment B city car, there is no clear sweet spot. This is because they are generally very light and efficient to begin with. But they are constrained by volume not weight. The sweet spot today is ~300km range with a ~40kWh battery weighing 1200kg.
For a compact car, the sweet spot seems to be around 400-450km with 62-72kWh battery weighing 1600-1700kg.
For a mid-size SUV, the sweet spot is 400-450km with 75-90kWh battery weighing 2000-2100kg. These are the specs bZ4X/RZ450e should have aimed for if they wanted to be competitive. And indeed we see majority of their competitors in this range.
For a full-size SUV it's hard to say because they are already too heavy and already suffer heavily from diminished return. I would say it's 450-500km with 110-125kWh battery weighing 2600-2800kg.
And pickup trucks are just stupid. With current technology there is no way to build an EV truck with reasonable weight and cost. That's how we got inefficient monsters like Rivian R1T and outright garbage like Hummer EV. A 300-mi truck needs a 130kWh battery and weighs 3 tons!