AllCell Automotive has released an innovative 48 volt micro-hybrid battery that can keep itself cool in a car parked in the sun on a hot summer day, solving a vexing problem that limits cycle life in typical micro-hybrid and start-stop batteries. The average car spends up to 95% of its life parked, and on the hottest of summer days temperatures inside a parked car can reach 70 C, a temperature at which batteries rapidly deteriorate.

AllCell's micro-hybrid battery utilizes a proprietary passive cooling material to absorb heat, continuously protecting cells from overheating for hours at a time, and is designed for easy integration across a variety of vehicle platforms. The new battery will debut at The Battery Show this week in Novi, MI (Booth #B1308).

Thermal management is critical to improving both safety and performance of micro-hybrid batteries. The key to AllCell's micro-hybrid battery is its composite phase change material (PCM) which requires no power to operate and has no moving parts. AllCell's PCM absorbs and evenly distributes heat whenever the battery is subjected to hot conditions, regardless of whether the car is turned on.

The combination of absorbing heat and limiting the maximum temperature allows automakers to eliminate active cooling systems while significantly extending battery life. AllCell's PCM is manufactured from inexpensive wax and graphite materials, which add little cost to the total battery.

Automakers are grappling with the downsides of traditional thermal management methods, including high cost, added complexity, increased weight and bulk, and inability to protect the battery when car is not turned on.

Unlike these complex cooling systems, AllCell's passive thermal management system keeps the battery temperature below 40 C even in very hot environments. In addition to increased cycle life, AllCell's PCM also stops the propagation of thermal runaway within the battery, a valuable added safety feature.

AllCell's 48 volt micro-hybrid battery has a 15 Ah nominal capacity with 16 kW maximum discharge power and 19 kW maximum charge power. With a total volume of 10 liters and weight of 10 kilograms, the battery offers a large improvement over comparable lead-acid batteries.