5. Macintosh Portable
The Macintosh Portable was a predecessor to today’s sleek MacBook models. It was released on 1989 with excitement from most critics and experts, but unfortunately it had very poor sales. Its battery was made from sealed lead-acid cells, which prone to fail if fully discharged. Original battery was very rare, because the production was stopped too early. The Macintosh Portable was also plagued by low readability in dim environment and Apple released an improved backlit Macintosh Portable in 1991, which cut the battery life in half.