The lithium-ion battery industry is expected to grow rapidly in the next decade, due to the increasing demand for electric vehicles and other electronic devices. Modern batteries frequently operate in challenging environments, making them susceptible to internal and external deterioration. It is imperative to develop standards to ensure safe operation of battery packs.
As advancements are made in Li-ion battery technology, the energy density of batteries has also been increasing, thereby elevating the likelihood and magnitude of potential battery malfunctions. Despite extensive knowledge about battery functioning, the significance of battery vents is often overlooked. This article delves into the necessity of a battery vent and its benefits for battery safety.
Battery packs are sealed enclosures that go through changes in temperature due to the battery electronics generating heat, charging & discharging, as well as varying ambient temperatures and operating altitudes. A change in the operating environment leads to a change in the pressure in the enclosure.
Batteries are fabricated from various chemicals which are critical to their functioning. Specifically, when discussing Li-ion batteries, gases like hydrogen and carbon monoxide are liberated due to decomposition, redox, and other reactions that occur during a thermal runaway event.
A battery vent is a safety component that avoids pressure & gas build-up and allows air and gasses to pass through and escape from an enclosure.
In essential conditions, battery packs need vents to keep the pressure equalized inside the battery pack and to prevent the battery pack temperature from rising to dangerous levels. Batteries and their electrical components generate heat in normal running conditions as well. It is vital to keep the pressure equalized for safe and efficient performance.
Pressure build-up, accumulated gases, thermal abuse, over-charging, mechanical damage, and electrical damage to the battery pack can trigger undesirable exothermic reactions that can lead to a thermal runaway event, where battery materials start reacting and generating uncontrollable heat. Thermal runaway events can result in extremely high temperatures, smoke, fire, and explosions.
Pressure Release Vents for batteries allow swift and efficient expulsion of gases generated during a thermal runaway event to escape the enclosure in a short time frame to prevent potentially dangerous situations.
PTFE is a microporous material that is chemically inert and can withstand harsh battery environments. PTFE membranes allow air to pass through due to the microporous structure, and at the same time, repel water, dust, and other contaminants. PorVent® PTFE Vents are IP67 rated and are available with Hydrophobic as well as Oleophobic properties.
PTFE Vents, unlike mechanical vents, equalize pressure continuously, as they do not need a certain pressure level to start operating. This ensures consistent and reliable venting performance and prevents gas and pressure build-up during normal as well as critical conditions. Constant pressure equalization also helps in preventing condensation, which can corrode and damage electrical components in a battery pack.
During a thermal runaway event, the PTFE membrane in PorVent® Pressure Release Vents has the capability of bursting, which helps gases to escape quickly through a barrier-free opening, preventing explosions.
In conclusion, battery pressure release vents play a vital role in safe and efficient battery pack performance. Constant pressure equalization, protection of electrical components, and most importantly – safety are the primary functions of a battery pressure release vent. PorVent® Pressure Release Vents also help battery manufacturers meet industry standards.
We, at PorVent® aim for a safe EV Ecosystem, which is very important for the growth of this industry.
Please visit www.PorVent®.com to explore PTFE venting solutions.