We've been looking at the stats for shield cell banks and have made some tweaks, which should filter out in a near future update. Basically, cell capacities have been reduced, cost per cell has been increased, and the passive power draw for having a cell bank active has increased.
We're not totally convinced this is the end of tweaking shield cell banks, but we think it will be a move in the right direction.
The main reason we're tweaking the shield cell bank is simply because we think our initial numbers were a bit messed up.
I think it's fair to say that a shield cell bank will potentially give a combatant a significant advantage in terms of survivability even after our changes. The way they work has not fundamentally changed at all.
However, before the tweaks, their various costs failed to update in line with other values, making them fairly ridiculously good value, which was never the intention.
We have not made the changes to make shield cell bank better or worse for two individual ships in a duel. We have simply made their running costs more in line with the benefit they offer. For example, the cost of a shield cell was basically silly, so we've increased it significantly. The cost of running a cell bank was negligible, so we've increased the power draw. But the ability of a cell to charge shields is unaffected. And larger ships can still basically fit more cell banks than smaller ships.
Looking at things objectively, the game is full of asymmetric conflict: a hauler is going to struggle against any combat ship, for example. Even if we wanted to balance the ships for one versus one battles, we would struggle like crazy.
AI using shield cell banks is something I really hope we get around to adding (it's in the "big list of cool stuff").
The advantage of a shield cell is primarily defensive in nature. Of course, in a perfectly matched battle between ships otherwise equal, the cell bank, if used at the right time, is a very large advantage.
However, their main advantage is that they allow you to not die, which is not quite the same thing as being victorious. If you are being outgunned, chances are that cells aren't going to tip the battle completely in your favour. But they can prolonge the fight, potentially giving all combatants more time to obtain/retain the upper hand.
This is why rather than simply remove them, or add in an arbitrary limitation of modules, I'd prefer to first explore more subtle rules that injected more player skill, in terms of timing their use, so that you could still use many of them, but if you use them "poorly" their benefit might be reduced, removed or countered by some other penalty.
My first line of thought runs to some additional negative effect that triggers if a cell is used and the shield is not badly damaged, coupled with a longer delay between triggering a cell and receiving its benefits. In theory, this would mean that you would need to use a cell within a window of opportunity or risk A) leaving it too late and having the shield break or B) using it too soon and having something bad happen (like damage to your shield generator, or no benefit of the cell, etc.)