Used EV Battery Degradation in Australia: Why It’s Not the Deal-Breaker You Think

Battery degradation is one of the biggest concerns holding Australians back from buying a used electric vehicle, especially for drivers who rely on their car to earn an income. You’ve likely seen the claims online: “EV batteries fail early”, “Replacement costs are huge”, or “Used EVs don’t hold range.”

In 2026, real-world Australian data tells a very different story.

Modern EV batteries degrade slowly, predictably, and far less than most people expect. Data from global fleet studies (combined with Splend’s own high-kilometre EV fleet) shows that used EVs remain practical, reliable, and profitable for years, even under demanding professional use.

This guide explains how EV battery degradation actually works, what real Australian data shows, how battery health affects everyday driving, and why battery concerns shouldn’t stop you from buying a used EV.

Why used EV battery degradation worries buyers

Australia’s EV adoption has accelerated rapidly since 2023, but battery anxiety remains common, particularly in the used market. The most frequent concerns include:

• Fear of sudden battery failure

• Uncertainty around replacement costs

• Confusion about range loss over time

• Worries about fast charging and heat in Australia’s climate

• Lack of transparency compared to petrol engines

Surveys from the Electric Vehicle Council and consumer groups consistently place battery lifespan among the top reasons Australians hesitate to buy a used EV.

What’s often missing from these conversations is context and data from real vehicles with high kilometres driven in everyday conditions.

What EV battery degradation actually looks like (real data)

Battery degradation is not a sudden drop. It’s a gradual process that slows and stabilises over time. Large-scale fleet studies show:

• Average degradation of around 1–2% per year

• Many EVs retain 85–90% battery capacity after 5+ years

• Degradation slows significantly after the first few years of use

Splend’s own Australian fleet data supports this. Across high-kilometre vehicles such as the Tesla Model 3, Tesla Model Y and Polestar 2, Splend consistently sees:

• 94–95% average State of Health (SoH)

• Measured across vehicles driven daily

• Often used for rideshare and professional driving

• Operating in Australia’s busiest cities and varied climates

These vehicles experience exactly the type of usage people assume is “bad” for batteries — long daily distances, stop-start traffic, fast charging, and warm conditions — yet battery health remains strong.

Annual EV Battery Degradation Rate – Global Fleet Data

Based on large-scale fleet studies, including Geotab data. Actual degradation varies by model, usage, charging habits and climate.

Splend Fleet State of Health by Model (box plot)

Based on battery health data from Splend’s Australian EV fleet. Results reflect real-world, high-kilometre vehicle use. Actual State of Health varies by model, driving conditions, charging behaviour and time in service.

What battery “State of Health” really means for everyday driving

Battery health is usually measured as State of Health (SoH), a percentage that compares a battery’s current usable capacity to when it was new. In practical terms:

• 95% SoH means you still have 95% of the original usable energy

• 90% SoH usually results in only a small, barely noticeable reduction in range

• 85% SoH remains well within the needs of daily driving and rideshare work

For most drivers, a reduction from 100% to the low-90s does not change how they plan trips, run shifts, or earn money. Range doesn’t disappear, it tapers slowly and predictably.

Based on battery health data from Splend’s Australian EV fleet, results shown include high-kilometre Tesla Model 3, Model Y and Polestar 2 vehicles.

Real-world Australian driving scenarios

One of the biggest misconceptions about EV batteries is that “real driving” destroys them. Splend’s high-kilometre fleet data shows the opposite: ordinary driving habits deliver excellent long-term battery health.

Case 1: High-kilometre rideshare driver (Sydney or Melbourne)

• Daily distance: 150–200 km

• Driving mix: Urban stop-start plus motorway driving

• Charging habits: Regular 40–60% top-ups, Occasional DC fast charging, Frequent AC charging overnight or at home

Expected SoH after 2–3 years: 92–96%

Outcome: No impact on earning capacity. Battery range remains more than sufficient for daily shifts, airport runs, and peak-period driving.

Why it matters: For rideshare drivers, the vehicle is a business asset. Knowing battery health stays in the mid-90% range even with high kilometres driven provides predictability, fewer surprises, and confident shift planning.

Case 2: Driver with no home charger

• Charging pattern: Public AC charging two to three times per week, Battery typically kept between 20–80%, Occasional top-ups at work or local charging hubs

Expected SoH after several years: Still in the mid-90% range

This aligns with Splend fleet results across high-kilometre rental EVs without access to home charging.

Why it matters: Many Australians assume EV ownership requires a garage and wall charger. Real-world data shows that with public AC charging and simple routines, battery health remains strong and predictable.

Battery SoH Distribution by Usage Type

Based on observed battery health outcomes across different usage profiles within Splend’s EV fleet. Results reflect real-world driving conditions and charging habits. Individual outcomes vary by vehicle, usage intensity and operating environment.

Does fast charging or heat ruin EV batteries?

This concern is especially common in Australia — and understandable. Modern EVs are equipped with advanced Battery Management Systems (BMS) that:

• Regulate battery temperature

• Control charging speeds

• Protect the battery from harmful conditions

Fast charging itself is not harmful when used appropriately. The key is balance:

• DC fast charging is ideal for long trips and time-sensitive top-ups

• AC charging is gentler and well-suited to routine use

• A mix of both reflects real-world driving and is standard across Splend’s fleet

Even in Australia’s warmer climate, active thermal management keeps batteries within safe operating temperatures, significantly reducing heat-related degradation.

EV battery warranties and buyer protections in Australia

Most EVs sold in Australia come with strong battery warranties. For example:

Tesla and Polestar have 8 years or 160,000 km and Guaranteed minimum 70% battery capacity retention

Importantly, independent fleet data shows most EVs remain well above this threshold throughout their practical lifespan.

Some manufacturers now offer battery health certificates for used vehicles. Splend can also arrange independent AVILOO battery testing, one of Europe’s leading EV diagnostic tools, providing additional confidence for buyers.

Splend can also arrange independent AVILOO battery testing

The cost myth: are used EV battery replacements expensive?

Online discussions often exaggerate battery replacement risk. The reality is:

• Battery replacements are rare

• Most drivers will never need one

• Degradation does not mean failure

When replacements do occur (typically well beyond average ownership periods) costs vary by model. Typical Australian estimates range from $5,000 to $16,000, depending on vehicle and battery size.

For context, major petrol engine or transmission failures can cost similar amounts, often without clear warning signs or health reporting.

Used EVs with verified mid-90% State of Health often retain value well because buyers know exactly what condition the battery is in.

How Splend removes battery uncertainty for used EV buyers

Splend specialises in EVs designed for real-world rideshare and high-kilometre use. Drivers benefit from:

• Verified battery State of Health data

• Clear explanations of real-world range, not just WLTP figures

• Optional independent AVILOO battery testing

• Charging support for renters and homeowners, including the Home EV Advantage Offer

• Vehicles selected for efficient battery chemistries and proven thermal management

Drivers don’t just get a car, they get clarity and confidence in the battery that powers their income.

Bottom line: should battery degradation stop you buying a used EV?

For modern EVs, the answer is clear: no.

Battery degradation is slow, predictable, and rarely affects daily driving or earning potential. Strong warranties, transparent health reporting, and real-world Australian fleet data show that used EVs remain practical and reliable for years, even when driving high kilometres.

Splend’s fleet proves it: EVs consistently maintain mid-90% State of Health, delivering dependable range and performance over time.