◄Previous: 7.2 Hybrid and plug-in hybrid vehicles

# 7.3 Full battery electric vehicles (BEVs)

Full battery electric cars require a larger battery storage capacity than hybrids or PHEVs.

In the 1990s, they were only available in small numbers as variants of ICE cars. (For example, the Peugeot 106 electric car, using nickel-cadmium batteries, was manufactured from 1995 to 2003). The Indian REVA G-Wiz micro car, using lead-acid batteries, was launched in 2001 and secured a small niche market becoming the world’s best selling electric vehicle in 2006.

The real change has taken place more recently. In the nine years between 2012 and 2021 global sales, PHEV and BEV vehicles increased by a factor of 50, with BEVs making up about 70% of the market.

A number of high-performance BEVs have been launched commercially, including the Nissan Leaf. This was initially produced with an 80 kW (107 hp) electric motor and a 24 kWh lithium ion battery, giving a range of 175 km. The battery size was increased in later models to 30 kWh.

As shown in Figure 12, the battery is fitted at the bottom of the car under the seats. The electric motor, control and charging electronics are all at the front of the car in the ‘engine bay’.

Figure 12: A cutaway of a Nissan Leaf BEV at a 2014 international trade fair

The US company Tesla has developed the high end of the BEV market. Their battery electric roadster, introduced in 2008, was fitted with a 56 kWh lithium ion battery. It had a top speed of 200 kph and an advertised range of nearly 400 kilometres.

Since then, Tesla has produced a range of different BEVs. In June 2021, their Model 3 saloon became the first electric car to sell more than 1 million cars worldwide. Tesla has managed to make the electric car an aspirational item of social status. The first electric Rolls Royce production model, the Spectre, was launched in late 2023.

Electric car sales in the UK have also been increasing rapidly. In early 2025 there were 1.4 million BEVs and 780 000 PHEVs. However this only represents less than 7% of the total number of cars in the UK.

## Activity 4

15 minutes

The 2010 Nissan Leaf was fitted with a 24 kWh battery and had a range of 175 km.

1. How many kilowatt hours of electricity would be needed for a journey of 50 km?
2. If the efficiency of the electric motor is 80%, calculate the energy used to actually move the car over this distance.
3. The energy density of petrol is 9.1 kWh per litre. An equivalent petrol-engined car has a fuel consumption of 5 litres per 100 km. Calculate the energy content of the petrol consumed in covering 50 km.
4. Assuming that the energy used to move the petrol car is the same as for the electric one, show that the thermal efficiency of the engine is 24%.
5. If the electric car is recharged with domestic on-peak electricity at 25 p per kWh and the petrol car is refuelled with petrol at £1.50 per litre, calculate the fuel costs for each car over 50 km.

(A text entry box would appear here, but your browser does not support it.)

### Answer

1. If the car uses 24 kWh for 175 km:

   energy used for 50 km = 24 kWh × 50 km / 175 km = 6.86 kWh

2. If the efficiency of the electric motor is 80%, the energy produced to physically move the car = 80% × 6.86 = 5.49 kWh

3. At 5 litres per 100 km:

   petrol consumed for 50 km = 50 / 100 × 5 = 2.5 litres

   Energy content = 2.5 l × 9.1 kWh l-1 = 22.75 kWh

4. If the physical energy used to move the vehicle is 5.49 kWh, thermal efficiency of engine

   = 5.49 kWh / 22.75 kWh = 24%

5. At 25 p per kWh, the cost for electric car

   = 6.86 kWh × 25 p per kWh = £1.72

   At £1.50 per litre, the fuel cost for the petrol car

   = 2.5 litres × £1.50 = £3.75

◄Contents►Next: 7.4 Charging infrastructure

OpenLearn - Transport and Sustainability
Except for third party materials and otherwise, this content is made available under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 Licence, full copyright detail can be found in the acknowledgements section. Please see full copyright statement for details.