Place the sleepbuds in the refrigerator for about 30 minutes after using them. Place sleepbuds into charger, Right sleepbud first.
Most of the time they show 100% charge for both. The right one still seems to go dead after about 6 to 9 hours. This is better than what I was having with the right one going dead after 2 or 3 hours.
I found this out after having them in the suitcase and in the truck of the car while it was around 50 (F) degress. They where both 100% charged and lasted all night! I had noticed that placing the right one in first was getting a higher charge rating before chilling them. I also tried placing the charging case into the refrigerator, but it flashes and does not charge.