Yes, these i-Eloop cars electrical system is very different than what we would call normal! The Mazda dealer has a special battery charger just for these systems!
Yes, my battery was not charging correctly. When my battery died over a week (cause still unknown) of non use, my hooking up a standard battery charger and charging it overnight may have brought it up enough to start and drive everyday but no where near a "full charge".
The dealer had to pull my battery and put it in a big vat of water, pull the caps, and charge it at a rate of 75 Amps for 5 straight hours! Yes, you read that right. 75 Amps for 5 hours! I pick up the car today and will try to get a pic of the charger they used.
If anyone has a i-Eloop car with a dead battery or a display that only goes to 3 bars (charging) and one bar (capacitor storage) you can not hook up a normal charger to it. You need to just jump the car (like normal) and drive it till it charges or have it towed to your local dealer for proper charging.
Some causes and symptoms for others having this problem:
Testing your battery with a standard battery tester (digital) my show your battery is charged, it may not be! Mine read good at the dealer with a regular tester. Only the Mazda OBD tester can test the "State of Charge". Mine was 16-18% but started and drove fine.
If your car load is over 50 Amps, you capacitor will not charge.
If the temp is below freezing it wont charge, not sure if that means capacitor temp or outside air temp.
EDIT! This car will in fact charge when below 32*!
Reference : https://www.mazda6club.com/threads/i-eloop-quit-charging.327769/
所以我揸多左幾日 依家見到i-eloop識差番上去