People are buying electric cars to reduce fuel costs and limit vehicular pollution, which is said to be one of the leading causes of climate change—the problematic growth of average global temperature.
Furthermore, electric vehicles (EVs) also allow their owners to use batteries instead of petrol or diesel. The advantage of using batteries is that they are rechargeable, allowing electricity to be stored to run the vehicle.
However, the problem is that EV batteries are expensive, at about INR 20,000 per 1 kilowatt hour (kWh). That is why replacing them will prove costly. Most EV batteries last around 10 to 20 years, or 160,000 km to 320,000 km. It is estimated that the capacity of EV batteries deteriorates by 2 – 3% per year.
The life of an EV battery also depends on other factors. An EV battery can be improved to a certain extent by not being exposed to extreme temperatures, opting for standard charging instead of fast charging, driving it at a steady speed, and following the recommendations of your carmaker regarding charging it.
What affects an EV battery’s life?
Major factors that impact the life of an EV battery are listed below.
1. Chemistry of a battery
- The major types of EV batteries are nickel-metal hydride (NiMH), lithium-ion, and lithium-titanium-oxide (LTO).
- Most electric vehicles use lithium-ion batteries, and their ability reduces over time. These batteries can reduce the driving range of an EV and their capacity to charge.
- NiMH batteries are primarily used in hybrid vehicles. Their lifespans can be longer than lithium-ions, but only if they are driven in moderate weather conditions.
2. Driving practices and maintenance
- Reckless driving can affect an EV’s battery life as more energy is consumed.
- The way you use it impacts the battery of your EV. For instance, if an EV’s battery is discharged and recharged frequently, it can also affect it in the long run.
3. Climatic conditions
- As stated above, extreme hot or cold weather conditions affect the chemical processes, quickening the battery’s ability to produce energy.
- The ideal temperature for EV batteries to have longer lifespans ranges from 20 to 30 degrees Celsius.
4. Factors Affecting Battery Life
| Factor | Impact on Battery Life | Description |
|---|---|---|
| Temperature | High/Low can decrease life | Extreme heat can degrade battery health |
| Charging Infrastructure | Frequent fast charging | Limited charging stations may impact charging habits |
| Driving Conditions | High mileage | Indian traffic and road conditions affect battery |
| Maintenance | Regular check-ups | Proper maintenance can extend battery life |
Electric Vehicle Battery Lifespan and Warranty Comparison in India
| EV Model | Battery Type | Estimated Battery Lifespan | Warranty Coverage | Estimated Degradation Over 8 Years |
|---|---|---|---|---|
| Tata Nexon EV | Lithium-ion | 6-8 years or 150,000 km | 8 years or 160,000 km | 15-20% |
| MG ZS EV | Lithium-ion | 6-8 years or 150,000 km | 8 years or 150,000 km | 15-20% |
| Hyundai Kona Electric | Lithium-ion | 6-8 years or 160,000 km | 8 years or 160,000 km | 15-20% |
| Mahindra e-Verito | Lithium-ion | 5-7 years or 120,000 km | 3 years or 125,000 km | 20-25% |
| Tata Tigor EV | Lithium-ion | 6-8 years or 150,000 km | 8 years or 160,000 km | 15-20% |
| Audi e-tron | Lithium-ion | 6-8 years or 160,000 km | 8 years or 160,000 km | 15-20% |
| Mercedes-Benz EQC | Lithium-ion | 6-8 years or 160,000 km | 8 years or 160,000 km | 15-20% |
The data in the table are estimates. Battery degradation rates vary based on factors like driving habits, charging patterns, and environmental conditions. Regular maintenance and sticking to manufacturer guidelines is the key to minimizing degradation.
Battery Degradation Rates
Battery degradation is a natural process where the capacity of the battery reduces over time. One needs to Understand the degradation rates to anticipate and plan for battery maintenance and replacement.
| Year | Battery Capacity Retained (%) | Notes |
|---|---|---|
| 1 | 95-98 | Initial slight drop after the first year |
| 3 | 90-92 | Gradual decline stabilizes |
| 5 | 85-88 | Consistent with average usage patterns |
| 8 | 70-80 | Near end of warranty period |
Procedures of maintenance
EV batteries do not require special care to maintain except when they are excessively charged and discharged.
Ways to charge EVs
There are three ways to charge EV batteries.
- With Level 1 charging, an electric vehicle is charged using a household electrical point. This is the slowest method, as it takes up to two hours to charge fully.
- For Level 2 charging, a 220-volt charger is required, which can be installed in apartment complexes, workplaces, and shopping malls, among other places. It works much faster than Level 1 charging.
- DC fast charging is the most rapid charging method available. It is used in public charging stations where users can charge and exit quickly, just like conventional petrol pumps. Here, charging an EV battery from empty to 80% of its charge takes up to half an hour.
However, more pressure is applied to the EV battery during DC fast charging than in the other methods. It is only used by individuals who travel long distances or for large fleets. As it is not for daily use, Level 2 is the best charging method for EVs to lengthen their battery lives. It is also recommended that a vehicle maintain at least a 3:1 ratio for fast vs. slow charging.
It is also suggested not to charge beyond an EV battery’s 80% capacity.
Practices to enhance the lifespan of EV batteries
Specific tips for maximizing the lifespan of EV batteries are stated below.
- Park it in your garage; do not expose it to outdoor conditions where the temperatures can be too hot or cold.
- Avoid haphazard and sudden acceleration of the vehicles. EVs need to be accelerated gradually.
- Follow the recommendations of your carmaker strictly.
- EV batteries function optimally with an 80% charge for those using their vehicles daily.