To alter or readjust; tinker with: sought to raise output this year by rejiggering its agricultural policies. [first form 1940s+, second 1960+; fr mid-1800s jigger, ''shake or jerk rapidly,'' related to jig as a rapid movement, dance, etc, hence ''rearrange or readjust by shaking,'' semantically similar to shake up]
AGM Batteries. Absorbent glass mat (AGM) is a class of lead-acid deep cycle battery in which the electrolyte is absorbed into a fiberglass mat. The plates in an AGM battery may be flat like wet cell lead-acid battery, or they may be wound in a tight spiral.
Just too expensive. More likely they are maintenance free flooded cell batteries or Gel batteries. AGM batteries would not need any special vent requirements. However, Home Power had an article several years ago called Battery Blunders and it showed 2 fellows looking over the remains of a fried battery bank.