The electric vehicle you bought might have "lost" 200 kilometers of range while you were sound asleep.

At night, your car was automatically upgraded.

You didn't know. You were sleeping.

When you turn on the navigation in the morning and plan to drive on the highway for 200 kilometers, you suddenly find that the remaining range is only 290 kilometers. Clearly, you could drive up to 470 kilometers when starting with a full - charge yesterday. Why is it nearly 200 kilometers less today?

This is not your illusion, nor is it battery aging.

This is your car being quietly "locked" while you were in deep sleep.

This is not a fabricated story. It is the common experience described by car owners in 12,000 complaints received by the national 12315 platform in March 2026, a year - on - year increase of 273%. (Source: CCTV.com, April 17, 2026)

What is OTA battery locking? Why don't you feel it?

OTA, short for Over - The - Air, literally means "over - the - air upgrade". Car manufacturers push software updates to your vehicle via the Internet, just like a mobile phone automatically updates apps. The whole process doesn't require you to go to a 4S store, plug in a cable, or even give your consent.

Battery locking is an operation to adjust a parameter in the battery management system (BMS).

The most straightforward way to understand this is to imagine that your fuel tank is marked with a capacity of 60 liters, but someone installs a partition in the tank without your knowledge, so you can only use 40 liters. All you can feel is that the range after refueling has become shorter, without knowing that the "capacity" of the tank has been reduced.

The specific figures come from real feedback from car owners: A car owner's vehicle was nominally rated with a CLTC range of 510 kilometers when purchased, and the fast - charging time from 20% to 80% of the battery was 40 minutes. After a nighttime OTA upgrade, the range was less than 300 kilometers, and the charging time was extended from 40 minutes to 70 minutes. (Source: Jiemian News, May 9, 2026)

From 510 kilometers to less than 300 kilometers. A difference of 200 kilometers disappeared during your sleep.

This is both a mechanism issue and a power issue:

Car manufacturers can change the core performance parameters of a vehicle through OTA software updates without the authorization of the car owner.

Why do car manufacturers do this? How is the profit account calculated?

Many people's first reaction is that car manufacturers are bad and deliberately deceive consumers.

But the actual situation is not that simple. Car manufacturers do this with industrial logic support.

The first reason: To reduce warranty costs.

The battery is the most expensive component of a new - energy vehicle, accounting for 30% to 40% of the vehicle's total cost. Excessive battery degradation means a large amount of warranty and battery - replacement costs. By limiting the charging and discharging range (for example, only allowing cycling between 20% and 80%), battery degradation can be significantly slowed down, and battery - replacement disputes within the warranty period can be reduced.

The second reason: To avoid safety risks.

Some batches of battery cells have a risk of thermal runaway under extreme conditions (high temperature, full charge, fast discharge). Limiting the charging upper limit or discharge rate through OTA is a soft safety patch. In a sense, this also protects the car owner.

The third reason: To cope with regulatory pressure.

The battery cycle life directly affects the vehicle's environmental rating and eligibility for government subsidies. Car manufacturers can maintain the performance under test conditions by locking the battery to slow down the degradation data.

The question is: Which of these three reasons was told to the car owner during the upgrade?

None. This is the core of the contradiction.

The purpose may be reasonable, but the means are opaque. This turns the whole thing from a "technical operation" into a "trust crisis".

Why is it so difficult for car owners to safeguard their rights? The "unequal" balance in the courtroom

At the beginning of 2026, a judicial big - data report on the China Judgments Online showed that in new - energy vehicle product liability disputes adjudicated by national courts from 2023 to 2025, more than 60% of car owners ultimately lost their lawsuits. (Source: Judicial data compiled by a Zhihu user, May 2026)

Why did they lose?

You say the range was 510 kilometers before battery locking and less than 300 kilometers after. Where does this comparison data come from? Who will verify it?

The car manufacturer's backend has records of each of your charging sessions, all parameter logs of the battery management system, and information on the OTA - pushed versions. And you only have a car and your words.

What's even worse is that car manufacturers can always attribute the battery - locking issue to other factors:

· Your driving habits led to the degradation.

· The temperature at that time affected the mileage performance.

· Natural battery aging is within the normal range.

The burden of proof is inherently unequal. All the key data is in the hands of the car manufacturer, and consumers are at a disadvantage from the start.

This is not because car owners don't work hard; it's a gap in the institutional design.

What does this mean for you? It matters to three types of people reading this article

Car owners who have already bought new - energy vehicles:

First, conduct a self - check. Look for OTA upgrade records in the vehicle's infotainment system or the official app, and compare the range performance before and after the upgrade. If you find a significant difference in the range after two full - charges, take photos and screenshots for record, noting the specific values and dates. This is your only means to safeguard your rights.

People who are still considering whether to buy a new - energy vehicle:

This is not a reason not to buy an electric vehicle, but it reminds you to read the OTA terms carefully when buying a car. Currently, the descriptions of OTA authorization in the purchase contracts of various car manufacturers vary greatly. Some are vague, and some don't even specify the authorization scope for "performance parameter updates" at all. This will be a key bargaining chip for consumers in the future.

Gasoline - powered car owners (this article is also relevant to you):

Do you think this has nothing to do with you? Your gasoline - powered car doesn't have OTA, but there are also many "unilateral modification clauses" in your insurance contract that you've never read carefully. This new - energy battery - locking incident is a public lesson on "consumer rights in the digital age", and others have paid the tuition for this lesson.

After regulatory intervention: They were summoned for talks. Then what?

According to CCTV.com, after the wave of complaints in March 2026, eight car manufacturers were ultimately summoned for talks by regulatory authorities. Three were investigated for violations, and two withdrew the controversial upgrade packages and promised to restore performance. (Source: CCTV.com, April 17, 2026; CNR.cn, May 9, 2026)

But then there was a reversal: The regulatory authorities never announced the specific list of the summoned car manufacturers, but some AI tools "imagined" the list, which spread widely on social media. Eight car manufacturers, including BYD, Tesla, XPeng, Li Auto, and NIO, immediately refuted the rumors collectively. The China Association of Automobile Manufacturers clarified that "the online content has no official source and seriously contradicts the facts".

This mystery reflects not only the problem of rumors but also a structural crisis of information opacity:

Because the regulatory authorities didn't announce the list, there was a public demand to know, someone used AI to "imagine", and there was room for the spread of rumors.

Transparency itself is the best tool to refute rumors.

Where are the boundaries of this issue?

OTA has real technological value, enabling vehicles to fix software bugs, add functions, and improve safety. There's nothing wrong with this in itself.

But the problem is that in the era of software - defined vehicles, car manufacturers have an unprecedented ability - **to change the core performance of a product you've already purchased without your knowledge**.

Currently, there is no clear legal boundary for this.

From the draft EU Automotive Software Safety Act to the current Chinese Provisions on the Administration of Automobile Data Security, relevant legislation is still in the catch - up stage. Questions such as "whether it involves core performance parameters", "whether separate authorization is required", and "where the boundary of consumers' right to know lies" still have no legal answers.

Before the law catches up, there is only one way to protect yourself:

Keep records of the range after each full - charge, the charging duration, and screenshots of OTA upgrade logs.

This is not redundant. It is the last card that consumers can hold for themselves in the digital age.

This article is only for information sharing and industry analysis and does not constitute any investment advice, investment analysis, or trading invitation. The market is risky, and investment should be made with caution. Any investment decisions made based on the content of this article will result in risks and profits or losses being borne by the individual. The author and the publishing platform will not assume any legal liability.

This article is from the WeChat official account "BT Finance" (ID: btcjv1), written by Shuyan, and is published by 36Kr with authorization.