I got the first gen di2 (7900 series) in 2010. Rode it for seven years. The junction box went out so I didn't ride it for three years, but I replaced the junction box this year. I kept the bike the whole ten years in my garage which gets very hot in the summer and fairly cold in the winter (East TN winters are usually mild, but we have single digit temps sometimes). Battery life is good and it still holds a charge.