If you need to travel with your bike, or just don't store it near an outlet then the Official Campagnolo EPS charger has some limitations. This removes some (but adds a few new ones, ie: slower charging). It includes a fully assembled electronics package in a 3d printed housing tested one multiple EPS systems. No USB cable or adapter is included.

I have multiple bikes with Campagnolo EPS and I love them, but the charger is very inconvenient. The short cable means a balancing act trying to figure out where to put the large original charger which wasn't designed for the charge connector placement of V3/V4. The other problem is that none of the electronic bike groupsets have a balance circuit. If your battery starts to become unbalanced it looks like premature failure. This won't re-balance it but it's slower charging rate will allow you to get more capacity into it.

It's tiny! It's smaller than Shimano's DI2 Charger. It's USB (micro). It works on a standard 500ma USB connector, so charge from anything! Also, if you're finding your EPS isn't lasting as long as you'd like slowing the charging can help to revive it because you can get more power in before it cuts off. Safety features include 8 hour max charge time, NTC that cuts off at 0 degree and 40 degree Celcius, and retains compatibility to the safety charging circuit in the EPS power unit (this is why there are a few "hacks" to the PCB in the photos).