A battery set is the key element for energy storage element in an Uninterruptible power supply. Either it is a short battery offering less than 5 minutes of runtime or a bigger battery pack covering many hours of backup, the battery setup would be focused on a lead acid battery. Lithium-ion battery technologies have progressed steadily over the past few years, powered by their demand within the electrical vehicle industry and for grid-scale energy storage.
Nowadays, the common valve-controlled lead acid (VRLA) UPS battery faces strong competition from lithium-ion suppliers. The reasons for this are many which are primarily due to the fact that lithium-ion (Li-ion) batteries are less temperature dependent, have a higher power capacity and are capable of nearly limitless charging and fast recharging cycles. As the development of lithium batteries has risen to satisfy increasing demand, the costs per battery block have decreased. We’re a long way from competition with UPS lead acid batteries, but the price difference will drop down easily in the next 5 years.
Recycling UPS Batteries
Many batteries will last up to 70-90 percent of their build life until they need to be replaced. Typical VRLA batteries used in UPS installations are either 5-year or 10-year design life items, which would need replacement approximately after 3-4 and 7-8 years. This depends on the ambient temperature at which they work, which should be 20-25 C, the number of charging/discharge cycles they run, and other considerations, including their architecture and output efficiency, and the complexity of their UPS battery charging circuit. Lithium ion batteries have a lifespan of 10 years or more.
VRLA batteries appears to have a plastic case that can or not be constructed from non-flammable components to BS 6290 part 4. Batteries reaching their end of life can be identified by visual inspection, UPS battery tracking devices and individual battery block checking.
Lead acid batteries are extremely flammable and provide heat while charging. They are highly exothermic and absorb heat upon discharging. The heating effect builds up due to the chemical reaction between the electrolyte of hydrochloric acid and the lead layer. The electrolyte appears to be a gel instead of a solvent in a VRLA battery. Usually, the glass casted batteries have a liquid electrolyte. Over time, heat will cause a plastic case to buckle and even break. White electrolyte compounds can also be found around the battery terminals.
When the battery has entered this condition, it is past its lifetime and is a possible danger to UPS installation in the form of a thermal runaway. The battery collection is still just as effective as its weakest battery block as the weaker battery decreases the cumulative output over time of the battery string.
Hence, Batteries should also be replaced before they enter this stage of physical decay. UPS battery tracking devices and periodic battery block tests will help detect failed batteries and the right time to schedule a battery replacement.
When the lead acid UPS battery is in touch or has a buckled or broken case, it should be handled as hazardous waste and in compliance with national legislation. In the United Kingdom, UPS battery recycling is highly regulated under the Waste Electrical and Electronic Equipment Recycling (WEEE) Regulation.
It is essential for the Contractors to get registered with the Environment Agency who transport such waste for health & security purposes. They must be highly skilled and trained for working within AC and DC power surroundings, managing batteries and hazardous material. Removed batteries should be taken to a registered recycling center.
90% of the recycled lead acid batteries material can be retrieved for later practice. The plastic cases made up of propylene can be recycled easily into new battery cases. Lead plates can also be melted down to reuse them into the new batteries. As well as, for other uses the sulphuric acid electrolyte can also be reclaimed.
Recovering UPS Batteries
Despite the on-site advantages of UPS or energy storage, the transport and recycling of lithium batteries poses more difficulties than lead acid batteries. The transport of lithium-ion batteries is forbidden in some situations where they are not part of the goods with which they are used. This is because they may pose a fire danger when weakened or exposed to water that can contribute to the creation of lithium hydroxide and hydrogen gas. Due to these reasons the airline transportation by UK airline is barred.
Summary
When you are looking at the Total Cost of Ownership (TCO) of the UPS system, it is important to select the UPS that will cover the entire life-cycle costs from deployment to eventual end-of-life dissolution. Lithium-ion batteries offer some benefits for room service and data center applications but have a higher retail price than VRLA batteries and higher end-of-life recycling costs. Such costs will decline over time and caution should be taken when deciding which form of UPS battery to be installed for new systems in the next few years. A method for the recovery and recycling of lead acid batteries within UPS systems has been developed and it is therefore necessary to work with a well-established and accredited UPS and battery recycling business.For more technical support or want to buy a perfect UPS system visit MultiLinkEng.com
