Apple collaborated with Chinese carmaker BYD for years on its now-cancelled car project, developing long-range EV batteries that laid the groundwork for current technology, reported Bloomberg. The partnership began around 2017.

Apple Inc. worked with Chinese automaker BYD Co. for years as part of its now-canceled car project, developing long-range batteries that helped lay the groundwork for technology used today, according to people familiar with the situation.

Before the Project Titan was scrapped, Apple reportedly worked with Chinese automaker BYD on custom batteries for Apple Car for years, but ultimately abandoned that partnership too.

As reported by Bloomberg on Wednesday, Apple has worked closely with Chinese automaker BYD. Both companies reportedly reached an agreement around 2017 to build batteries using lithium iron phosphate cells (LFP). The technology would significantly increase the autonomy of the car and was also considered safer than typical electric vehicle batteries.

Apple secretly collaborated with Chinese automaker BYD to develop long-range electric vehicle battery technology as part of its now-nixed Apple

For years, Apple was rumored to be working on a futuristic self-driving car, with the company tied to collaborations with Volkswagen and even a potential deal to buy McLaren at one point. That never happened and the project was canned after 10 years,

Apple (NASDAQ:AAPL) and Chinese automaker BYD (OTCPK:BYDDF) worked secretly for years as part of the technology firm’s now-canceled car project, Bloomberg reported, citing people familiar with the situation.