New fast-charging technology, which was a missing component in the early development of electric vehicles, is partially to blame for the continued electrification of transportation.
Fast-charging systems facilitate the switch to electric vehicles, but their use requires careful supervision.
Why?
Heat is the main byproduct of rapid charging, particularly when AC to DC electrical current conversion occurs. Heat is the worst enemy of electric vehicle battery packs and a direct danger to the security of EV charging stations.
Any size of EV lithium-ion battery is intended to operate in the 15–45°C temperature range. An EV battery’s health is negatively impacted by exposure to high temperatures outside of that range, which can affect its:
- Capacity to hold a charge: Extremely low ambient temperatures can damage batteries during charging by causing dendrite formation, and overheating can significantly impair a battery’s capacity to hold a charge.
- Charging capacity: An EV battery pack’s capacity is lowered by exposure to high temperatures. There is less to charge when there is less lithium present.
- Practical life: Any size of rechargeable battery, from AAA to those powering an airplane, is made to last for several thousand charging cycles. A battery’s useful life can be shortened by several years due to damage caused by excessive heat.
- Safety: Thermal runaway, a series of events that could ignite a fire, is caused by the breakdown of overheated EV battery cells.
THREE PLACES EV SENSORS ARE NECESSARY TO MONITOR FAST CHARGING
Sensor technology is the first step toward ensuring the safety and effectiveness of high-speed EV charging. Fast-response sensors, particularly vehicle temperature sensors, are necessary for fast charging.
The possibility of heat-related damage to an EV’s components rises sharply in the absence of real-time monitoring that activates the systems responsible for maintaining optimal temperatures.
Temperature sensors are required in three locations within an electric vehicle in order to facilitate fast charging:
- Charge handle Connection point
- Thermal management system
- Inside the battery pack
1. THE CONNECTION POINT
The charging port and the charging handle are the two locations at the point of connection where temperature sensors are essential.
Many electrons must swiftly move from the EV service equipment to the vehicle battery in order for the battery to charge quickly. There’s heat from this high current. Elevated temperatures within the charging port might suggest an inadequate connection between the EV’s contacts and the charging handle. A bad connection reduces the vehicle’s efficiency by preventing it from charging as quickly as it should. High temperatures coming from the connector of an EV quick charger can also indicate that the charger is beginning to malfunction or that the power demand is overloading it.
2. The system of thermal management
An EV’s thermal management system overheating is an instant indicator that something is wrong and that its parts are getting too hot to handle, such as:
- Heat exchangers
- Cooling plates
- Coolant fluids
- Refrigerants
- Dielectric oils
High temperatures can also indicate that the parts of the EV that the cooling system is meant to be cooling are producing too much heat.
3. INSIDE OF THE BATTERY PACKAGE
An EV’s battery pack, which is arguably the worst place for overheating, needs to be maintained between 15 and 45°C to ensure both integrity and safety. When charging, lithium-ion batteries do best in the 45–60°C range, but they can become slightly damaged in higher temperatures. The car may enter safe mode, shut down, or, worse yet, initiate a battery thermal event if the inside temperature rises above that point.
A battery overheating is one of the last indicators that something isn’t right with the vehicle’s charging or thermal management systems, or the battery itself is malfunctioning.
To maintain the battery’s long-term functionality and safety, immediate cooling is a necessity.
THE FUTURE OF EV FAST CHARGING
The technology for fast charging is still in its early stages of development.
An EV’s battery can be recharged to 80% capacity in about 30 minutes using current fast-charging technology. Though it usually takes less than ten minutes, engineers are still striving to make fully charging an EV equal to filling up an automobile’s empty gas tank.
Convenience isn’t the only factor driving the need for ultra-fast electric vehicle charging. Ultra-fast charging, which could make vehicles mobile in a matter of minutes, is all but required by ground transportation companies and those with fleets of large vehicles (buses).
- Simply put, the battery packs in larger cars are larger than those in electric cars by a factor of several. Their charging time is longer. However, charging time equates to lost revenue and productivity.
Quick-response sensors that track temperature inside an electric vehicle are essential for:
- Restoring automobiles to service more quickly
- avoiding damage or deterioration of batteries
ELECTRIC VEHICLE SENSORS & FAST-CHARGING SYSTEMS: A NECESSARY PAIRING
Even though the electrification of vehicles represents one of the largest shifts in transportation history, owners and operators still have certain expectations regarding functionality. This change is being made possible by fast-charging technology, which directly addresses a serious concern for the operation of EV charging stations and vehicles.
The unsung hero of electric vehicle charging is its sensors, which make the process as simple as filling up the tank.