Porsche is investigating allegations that lithium-ion battery packs in its electric vehicles are faulty and could catch alight.
Six out of 10 of the company’s Taycan vehicles reportedly have issues with battery management that affects and damages cells, according to reports by media outlet Teslarati.
Teslarati quotes a “whistle-blower” working at Porsche’s headquarters in Zuffenhausen, Germany that the issues require replacement of cells and batteries, and are causing vehicle fires.
Although reports on Taycan fires are rare, the first known incident happened in February, 2020 in Florida, US.
In July, Porsche recalled 43,000 Taycans over concerns faulty software could cause the battery-powered engine to suddenly shut down.
A Porsche spokesman told BEST: “On Wednesday, December 1st, 2021, Porsche was confronted with various allegations regarding the Taycan in an article on teslarati.com.
“The allegations are currently being investigated. Please understand that we are currently unable to comment on this.”
According to the report, the Taycan’s “inexpensive” onboard charger “does not control the charging process well enough and can overcharge some battery cells, causing them to overheat”.
For safety reasons, overheated battery cells are disabled and isolated from the battery pack, reducing battery capacity and thus the vehicle’s range.
The Taycan’s problem occurs when the batteries are charged at a low AC speed of up to 7.5 KW, such as at home or on low-speed chargers, the report claimed.
Around 360 out of 36,000 Taycans vehicles delivered had a preventable vehicle, cable, or smoldering fire attributable to the problem, the report adds.
According to the report, the “whistle-blower” spoke out because Porsche has decided not to replace the Taycan’s onboard charger, but to continue shipping vehicles and all future new Taycan models with the problematic system.
EV battery concerns
It is not clear if the issue affects all models of the car, which cost from £78,000 up to £140,000.
The vehicle’s 800-volt architecture produces charge power of up to 270kWh and can be charged to achieve a range of 62 miles in six minutes, states Porsche.
Optimum charge conditions include: a CCS fast-charging pedestal with around 270kW/850-volt and at a battery temperature of 30-35oC and an initial charge status of 5%.
The Taycan is the first production vehicle with a system voltage of 800 volts instead of the usual 400 volts for electric cars.
This enables consistent high performance, reduces the charging time and decreases the weight and installation space of the cabling.
The two-tier Performance Battery Plus used in the Taycan Turbo S and Taycan Turbo contains 33 cell modules consisting of 12 individual cells each (396 in total). The total capacity is 93.4 kWh.
The system’s pouch cells are designed to allow optimal use to be made of the rectangular space available for the battery and a reduction in weight.
Read the full Teslarati report HERE