The SkelMod 51V ultracapacitor module is used especially in rail applications, such as kinetic energy recovery and peak shaving, but its versatility lends itself to many applications across industries. SkelMod 51V rail-certified ultracapacitor module has 51 V, capacitance of 177 F, 1 second DC Equivalent Series Resistance of 4.0 milliohm. The module uses 18 SkelCap SCA3200 ultracapacitor cells. It also has CAN bus communication, and an integrated ultracapacitor management system for cell balancing, natural cooling, and IP65 protection. It is currently the only rail-certified ultracapacitor module of its kind on the market.