There are many features of a battery storage system that you should be familiar with before you make a purchase. We've listed the top eight features to understand:
Charging cycles Batteries have different cycle lives – the number of times a battery can be charged/discharged over its lifetime.
Battery life All batteries will lose storage capacity over time, some quicker than others. Battery storage capacity and battery life are also impacted by how the battery is used and temperature. When you enquire about your battery storage system, ask about warranty periods and disposal costs at the end of battery life. Generally your battery storage system will last for 5 to 15 years.
Usable energy The usable energy of your battery storage system is what needs to match your electricity needs. However not all of the energy a battery stores is available as 'usable energy' in your premises. The amount of usable energy (or 'typical cycle capacity') can range from 30% to 80% of the battery's energy storage capacity. For example, one battery may have a total energy storage capacity of 20kWh and a cycle capacity of 80%, and therefore 16kWh is available as usable energy. Another battery may have a total energy storage capacity of 20kWh and a cycle capacity of only 50%, and therefore only 10kWh is available as usable energy.
Safety There is a wide range of battery storage systems and they can all differ in their technical safety. Misusing the battery or not having the correct battery management system might put stress on the system, making it more vulnerable to fail or in some cases start a fire. Check with your battery installer and other sources for the technical safety of your proposed battery storage system. Also be aware that batteries can present dangers if that part of your premises was to catch fire. Do not use your battery if there is ANY damage to the battery enclosure or the battery.
Temperature Different batteries are suited to different climates, but most batteries do not like very high or very low temperatures. When installing the system, make sure there is good ventilation, no direct sunlight or exposure to the weather. Choose a battery technology that can cope with the temperatures your premises is likely to experience.
Battery management system A battery management system is used for some types of batteries. A lithium based battery must have a battery management system. The battery management system ensures that the flow of energy in and out of the battery does not harm it. It also ensures that the battery does not overheat. Other battery systems, for example a lead acid based battery, do not require a battery management system and the charger (or inverter) controls the amount of energy flowing in and out of the battery. If a battery’s charge and discharge is not well managed, the battery life may be shortened and the battery may fail.
User interface Some battery storage systems have a user friendly interface via a front screen and some use a smart phone app (or similar). A monitoring system can be used to check how your system is operating. You may need to provide an internet connection for your system.
Inverters Your battery storage system will connect to the grid and your premises through an inverter. The inverter converts the direct current (DC) power of your battery to the alternating current (AC) power suitable for your premises. AC power is supplied from the inverter at 240v (+/-6v) – the voltage generally used by appliances in homes and businesses. The inverter should be sized to suit your energy needs and the battery system requirements. It must be able to talk to the battery management system and be compatible with your battery.