Fast Charging Station Failure Statistics (2025): What Percentage Is Related to DC Contactors?

As the number of electric vehicles continues to surge, public DC fast-charging stations are expanding rapidly. But the more widespread fast charging becomes, the more visible the problems are: charging failures, unavailable chargers, over-temperature shutdowns… all of these issues affect the user experience.

Among many causes, the DC contactor is actually one of the most overlooked components.

A common question from engineers and operators is:

How many fast-charging failures are actually caused by contactor issues?

Based on publicly available reports and industry information from 2025, this article provides a clear breakdown.

Why Do Contactors Become “Hidden Critical Components”?

Inside the high-voltage circuit of a DC fast charger, the contactor performs one essential job:

Safely connecting and disconnecting hundreds of amperes at several hundred volts of DC.

It is essentially the system’s main switch + safety gate.

When something goes wrong—minor issues lead to charging failure, and major issues can cause overheating or electrical hazards.

Some of the latest charging systems even include “contactor status monitoring” in their patents and safety controls, highlighting how seriously the industry now takes this component.

General Fast-Charging Failure Trends: Many Problems, Poor Categorization

In 2025, multiple organizations released data on fast-charging station performance. For example:

A U.S. EVSE reliability study showed that

the first-attempt charging failure rate remains at 25%–30%.

J.D. Power’s 2025 analysis reported that users still frequently face

charger unavailability, interrupted sessions, and failed charging starts.

These findings all point to the same conclusion:

Fast-charger instability is widely recognized, but the root causes are rarely broken down in detail.

Most reports mention vague categories such as hardware failure, communication issues, over-temperature, or charger unavailable.

They almost never specify: “How many of these failures were caused by the DC contactor?”

Is There Any Public Data Showing the Contactor Failure Percentage?

The short answer: No official and accurate statistics exist.

And the reasons are clear:

1. Failure categories are too broad

Operators usually record only “charging/not charging.”

You will almost never see categories such as “contactor welding” or “coil actuation anomaly.”

2. On-site diagnosis is difficult

Contactor issues can be subtle and require specialized testing.

Many faults like “charger won’t energize” or “frequent drop-outs” may be contactor-related but never explicitly labeled as such.

3. Manufacturers do not publish detailed internal failure data

Even if internal statistics exist, they are rarely disclosed publicly.

So What Can We Reasonably Infer?

Although no official percentage is available, real-world industry observations show:

Among hardware-related failures, the contactor is a common but not the largest cause.

The higher the power and voltage level (especially in 800–1500V systems), the more stress the contactor faces.

Many “hard-to-explain” failures—such as:

Intermittent energizing failure

Charging session unable to start

Frequent thermal shutdown

Abnormal switching sound

—are often linked to contactor degradation or inconsistent behavior.

In other words:

Contactor problems are a representative failure type, but not yet fully quantified.

If you're expecting a precise number—something like “DC contactors account for 12.6% of fast-charging failures”—unfortunately, no such figure exists today.

Not because contactors are unimportant, but because:

Failure logging isn’t granular enough

Diagnostics are often inconclusive

Manufacturers hold the detailed data

Most issues get dumped into broad categories like “hardware failure”

But based on feedback from field engineers and maintenance teams:

Whenever a fast charger shows weird, occasional, or difficult-to-reproduce issues, the contactor is often one of the first components worth checking.

As fast-charging power increases and usage frequency grows, keeping contactors healthy will become increasingly important.

In the future, contactor-related issues may very well become a separately monitored failure category.