BYD Atto 1 and Atto 2 battery cooling in question as Atto 1 nabs five-star safety rating

At a glance 

• BYD confirms BYD Atto 1 and Atto 2 have no direct liquid coolant to batteries 
• ANCAP awards BYD Atto 1 a five-star safety rating 
• Social media reports suggest base-level Atto 1 has no active thermal management 

Attention has turned to how BYD manages battery temperature in its new small EVs. The Atto 1 and Atto 2 recently launched in Australia with a market-beating starting price of $23,990 for the smaller Atto 1, but there are concerns that its EV battery may not be up to the task of Australia's extreme summers. 

People on online forums and social media threads have been asking whether the BYD Atto 1, particularly the base variant with its smaller battery, might follow the path of early EVs such as the pre-2025 Nissan Leaf, which did not use liquid cooling for the pack and saw higher rates of degradation in hot climates. 

It is important because in extreme temperatures, EV batteries that are not effectively managed will lose driving range and potentially degrade faster. While BYD’s Blade batteries are highly regarded in the industry, reduced range particularly in a short-range vehicle raises questions about its suitability for the Australian market. 

In response to questions about thermal management for both Atto 1 and Atto 2, BYD responded to Open Road saying that: 

• Automatic active thermal management via software: The Atto 1 and Atto 2 use automatic active thermal management overseen by software. There is no in-car menu option for the driver to switch battery heating or cooling on or off. 
• No direct liquid coolant circuit to the battery: BYD says there is "no coolant going to the battery.” 
• No manual battery preconditioning: Drivers cannot manually trigger preconditioning in the car or via the app. 

That means the Atto 1 and Atto 2 sit somewhere between the early “no thermal management” EVs and the typical liquid-cooled setups used by many current rivals. The vehicles do, however, use BYD’s e-Platform which includes a heat pump that assists with the power battery cooling, as noted in this tech breakdown. 

Why the Nissan Leaf comparison matters 

The pre-2025 Nissan Leaf comparison is topical because it used a relatively simple thermal approach with no active liquid cooling for the battery. In cooler regions that was less of an issue, but in hot environments, owners reported faster capacity loss and more noticeable range decline over time, especially when the cars were fast charged frequently or driven hard in high ambient temperatures. 

That experience has left many EV buyers wary of any new model that appears to skip liquid cooling for the pack, particularly in countries where summers can be extreme and highway runs often involve long distances at 100km/h or more. 

BYD’s answers do clear up some of the speculation that Atto 1 might ship with no active pack management at all. However, there are still questions that matter for Australian conditions, including: 

• how aggressively the system cools the pack during repeated DC charges in high heat 
• what temperature thresholds the car targets for battery longevity versus charge speed 
• whether there are any differences in thermal hardware or strategy between Atto 1 and Atto 2 trims sold here 

We have reached out to BYD for further clarification and will update this article if more information is received. 

BYD Atto 1: Five stars for safety 

Meanwhile, ANCAP has awarded the new BYD Atto 1 a maximum five-star safety rating, giving Australia’s cheapest new EV a strong start on the safety front even as questions remain about how its battery is cooled. 

The rating applies to both Atto 1 variants and puts the compact hatch in line with bigger, more expensive electric models on core crash and safety assist metrics. At the same time however, BYD has confirmed that neither the Atto 1 nor the larger Atto 2 use a conventional liquid coolant circuit to manage battery temperature, something many buyers have come to expect in modern EVs. 

ANCAP’s scores for the BYD Atto 1: 

• 82% for Adult Occupant Protection
• 86% for Child Occupant Protection
• 76% for Vulnerable Road User Protection
• 79% for Safety Assist 

Standard safety kit across the range includes: 

• Autonomous Emergency Braking
• Lane Departure Assist and Emergency Lane Keeping Assist
• Intelligent Speed Limit Control and Forward Collision Warning
• Tyre Pressure Monitoring System
• A direct driver-monitoring system 

The Atto 1 is available to order from $23,990 before on-road costs, with both trims covered by the new ANCAP result. While the Atto 2 has not yet been tested by ANCAP, it does get (in addition to the Atto 1’s safety offerings) more safety kit including: 

• Electric Parking Brake System
• Hill Descent Control 
• Lane Departure Warning 
• Rear Collision Warning 
• Rear Cross Traffic Alert and Brake 
• Blind Spot Detection 
• Door Opening Warning 
• Intelligent High Beam Control 

The bottom line for buyers 

For now, the Atto 1 enters the market with a strong ANCAP score and confirmation from BYD that its battery is actively managed via software, even if it does not use a conventional liquid coolant circuit. 

Budget-conscious buyers get a five-star-rated compact EV with a full set of safety and driver-assist features. On the thermal side, whether or not the batteries in the budget Atto range will perform adequately in the Australian climate is in question. Until more is known about how the Atto 1 and Atto 2 battery health holds up, it will be worth paying close attention to real-world reports, especially from drivers who fast charge often or regularly travel long distances in high temperatures.