Yes, really. The maintenance free nature of ultracapacitors is what gives them significant advantage over batteries, specifically in applications that are hard to reach or where downtime could prove costly. Imagine what would be involved in having to perform battery maintenance on a satellite. Talk about hard to get to! Another example is turbine maintenance on wind-farms, where battery-based emergency pitch-control systems cause downtime hours on a monthly basis.
Ultracapacitors are energy storage devices that stores energy electrostatically. On the contrary, battery technologies such as lithium-ion batteries store energy electrochemically. Ultracapacitors have wide operating ranges of voltage and temperature, and when used within these broad parameters there is no recommended maintenance.
So, what actually enables ultracapacitors to be maintenance free?
They have no memory effects | Memory effects occur in most rechargeable batteries. The maximum capacity of a battery is reduced if they are frequently recharged after only being partially discharged. This also results in a decreased life. This is not the case with Ultracapacitors.
They have high stability | Due to the high cycle stability of ultracapacitors (being greater than 500,000 charge and discharge cycles), energy storage units with ultracapacitors have a long service life and therefore are practically maintenance free.
They cannot be over-discharged | Over-discharging occurs when a battery is discharged below its minimum design limit. This results in a loss of overall capacity and reduction in life. Ultracapacitors can be discharged to zero energy with no ill effects.
They do not involve chemical reactions | Ultracapacitors use physical adsorption of ions to store energy, rather than chemical reactions like batteries. The complex chemical reactions that take place in batteries can cause them to degrade or fail over time which is not the case in ultracapacitors.
They are resistant to temperature variations | Ultracapacitors can operate over a wide temperature range. They are highly resistant to temperature variations whilst maintaining their performance and capacity. Unlike batteries that require complex charging discharging strategies over a reduced temperature range.
Overall, the maintenance-free aspect of ultracapacitors is a key advantage of these devices and makes them an attractive option for a wide range of applications, from automotive and industrial systems to consumer electronics and renewable energy systems.