Make accumulator a passive network element with only one connector (two connectors logic is too cumbersome).

• When there is more energy than needed in the network - accumulator is charging
• When there is not enough energy in the network, the accumulator should discharge stored energy.
• When accumulator is powered by redstone signal it should not discharge (but it should always charge)
• Charging/discharging accumulator should produce some particles or change texture to give some info about what's happening.
• Integrate showing accumulator capacity and stored energy into engineering goggles as KFET - Kilo-FE-Tick as an analogy to KWH. Also show in the tooltip accumulators charge and discharge rate.
• Be able to pickup charged accumulator
• Be able to read with comparator energy stored / capacity of accumulator

1-2 is hard to implement and get working of blocks from other mods.
3 Use a Redstone Relay.
4 Maybe in the future
5 was added in 20210625a.

1-2 is not currently possible, I'm planning to rework the energy system which could enable this.
3 could be done
4-5 would require additional networking syncing with the client. If I figure out a performant way to do this I will.
6-7 are already features