Ultimate Battery (GregTech 5 Unofficial)/en

The Ultimate Battery is a Battery added by, capable of storing 9 sextillion EU, which is exact Long.MAX_VALUE or 9,223,372,036,854,775,807 EU. It is a UV Battery (524,288 EU/t).

To completely fill it at 524,288 EU/t it takes 879,609,302,220 Seconds or 10,180,663 Days or 27,892 Years!