Growing Battery Industry Brings Growing Concerns

on March 28, 2017 at 8:13 AM

General Images Of Electric Vehicle Recharging And Battery Changing Station In BeijingAs renewable energy sources become more extensive across the world, the need for battery storage systems has suddenly become a forefront issue. However, the security of such storage units is rarely a part of the discussion – each system poses significant hazards. Safety comes in the form of innovative management systems as well as high-quality cells.

Austria provides an example of this growth, where the total installed capacity of photovoltaic systems exceeds 1 gigawatt – only a fraction of which is equipped with battery storage units. These units, however, are essential in the ongoing transition to renewable energy sources. They allow individual consumers to use and store their own self-generated energy, even during intermittent times. This relieves pressure from the consumer grid.

The batteries allow individual households and businesses to increase their self-consumption. Further, excess energy produced by their systems can be sold to the national grid to help regulate fluctuations during peak hours of demand. Batteries are the key to a decentralized power system. But the question remains: are they safe?

Because the battery market is growing at such a rapid pace (largely in part due to industry mega-players such as Tesla), there is a tendency to forget how young the market is. Only 10 years ago there were individual manufacturers producing their own batteries and connecting them to PV plants without and safety or quality assurance standards. Quality back then was questionable to say the least.

In 2015, the Karlsruhe Institute of Technology (KIT) proposed a solution to this problem. The German institution published its “Safety Guidelines for Lithium Ion Household Storage” with help from leading industry players. The goal was to guide the market on safety standards. The guidelines have help improve the quality of residential battery systems. However, as it stands, only a few storage devices have earned independent, external certification that confirm they meet the guidelines and safety standards set forth by KIT.

Lithium-ion batteries surpass the performance of lead-gel or lead-acid batteries on several different fronts. Efficiency, discharge, and storage capacity are significantly higher for li-ion. This is in addition to the fact that they produce more full cycles in their usable lifetime. Lithium ion also has a higher energy density, meaning more energy can be stored in a smaller amount of space. This reduces the physical size of the batteries and makes installation easier. Lithium ion batteries, however, still require adequate care and precision in their development and manufacturing, which is safety concerns are paramount.

One of the obvious safety concerns is temperature. Batteries and the cells that comprise them can only operate safely within a temperature range of -10 to +50 degrees Celsius (14 – 122 degrees Fahrenheit), depending on the chemical composition of the individual cells and electrodes. A cell that crosses either of these thresholds even once will be damaged, shutting down the entire battery.

Extreme temperatures can cause a chain reaction, known as a thermal runaway. These can cause gasses to escape, which can ignite a fire or else explode. These problems can also be caused by overcharging the battery, or using too much energy too quickly (known as deep discharge). The real challenge is avoiding the conditions that lead to these problems.

Avoiding these conditions, however, must be a responsibility shared between developers, buyers, and production managers. Quality and safety standards must be improved on the manufacturing front, but consumers also need to be educated on proper usage. This can be aided by intelligent control systems that prevent the battery from entering into one of these critical states. The battery management system should be able to detect when a cell is about to spoil and override.

In addition, the battery housing itself must be sound. Solid, fire-proof casing that can prevent gas leakages is necessary to prevent fires and explosions. And lastly, data security is a risk. The manufacture should be implementing cyber-security measures to prevent hackers from changing security parameters; these batteries are all connected to the internet to manage energy-sharing. The consequences of a hacking can destabilize the grid as we move towards decentralized storage solutions.