Is lithium the only solar storage option?

There's a growing buzz around battery storage. We all recognize the unpredictable climate where health crises and international conflicts can influence our energy costs. At the same time, we're striving to create a greener economy. Solar panels and energy storage are among the many solutions that can help minimize your environmental footprint and lessen your reliance on the grid.

When it comes to ENERGY STORAGE, what choices do you have? I'll explore the advantages and disadvantages of lithium batteries compared to AGM and GEL batteries. I will also examine the circular economy and the end-of-life plan.

 

AGE

Lead Acid:

Lead acid batteries have a long history, dating back over 160 years. They were invented by Alessandro Volta in the late 17th century and are commonly used in cars and motorbikes. The AGM technology emerged in the 1960s.

Lithium:

Lithium-iron batteries were first developed in the 1970s, with the first commercial model introduced in 1991.

 

RESOURCES AND ELEMENTS

Lead Acid:

An AGM or GEL battery contains several components: electrolyte, glass fibre separator, a grid made of Pb-Ca alloy, sulfuric acid, and lead paste consisting of lead oxide and sulfuric acid. The acid is primarily composed of water, while the electrolyte is synthesized in a laboratory. Lead is mined, mainly in Australia, and is not considered a rare mineral, making it relatively easy to extract. Recycled lead is used regularly in new batteries.

Lithium:

A lithium battery comprises lithium, graphite, cobalt, manganese, nickel, and adhesive. Four of these elements are mined, and the rising demand has led to increased mining activities, often with ethical concerns. Over half of the world's cobalt supply comes from the Congo, linked to human rights issues. Lithium extraction involves pumping brine to the surface, which poses significant environmental impacts on local flora, fauna and animals.

 

RECYCLING

Lead Acid:

An impressive 99% of an AGM or GEL battery can be recycled. Lead can be reused indefinitely without loss of capacity, while the acid is neutralised, and the plastic is melted to create new cases. This recycling process is reliable, yielding about a 10% payback for recycling your batteries, with numerous facilities available to facilitate the process.

Lithium:

Recycling lithium batteries presents challenges. Currently, there is no effective method for recycling them due to several factors:

1.            The adhesive used is exceptionally difficult to remove, requiring labour-intensive manual work.

2.            There is no standardised design for these batteries, complicating recycling practices.

3.            The UK lacks recycling plants capable of handling lithium batteries; crushing or smelting them carries a high fire risk. Since 2019, lithium batteries have caused 1,800 fires in recycling facilities.

While there are methods to design batteries for easier recycling, this is not currently the norm. Additionally, transporting damaged or used lithium batteries poses significant risks, and there is currently no market for recycled lithium.

RISK

Lead Acid :

Lead acid batteries are low-risk. They do not ignite, because their cases are engineered to melt. These maintenance-free batteries do not emit gases or fumes and are equipped with built-in flame arrestors. However, they should be stored in a ventilated space to prevent overheating. It is also essential to avoid overloading or overcharging, as this can cause swelling. If a fire occurs due to an external source, the battery will simply melt. Damaged batteries should be replaced promptly to avoid circuit issues.

Lithium:

Lithium batteries have a known risk of fire and can even explode in severe cases. When ignited, they produce a dangerous, toxic vapor cloud that can disperse. As lithium batteries age, they become increasingly volatile, leading to more incidents in recycling facilities. No specific fire extinguisher can effectively contain the accompanying vapor cloud. It can takes days for a lithium fire to go out. If a fire starts from an unrelated source, like a candle, the battery may ignite and explode without warning. Fire services are now issuing strict guidelines on storing lithium batteries, prohibiting placement in hallways, lofts, or blocking entrances. Historically, this area has been largely unregulated, but recent regulations are being established.

SIZE

Lead Acid:

AGM batteries are large and heavy, weighing between 25kg and 75kg. They require ample storage space in a ventilated area, and a modular system is ideal, often needing four to sixteen batteries for a robust setup.

Lithium:

Lithium batteries are significantly lighter, weighing about half as much as their AGM counterparts. Their compact size allows for more discreet installations, including wall-mounted options.

COST AND LIFESPAN

Lead Acid:

The average cost of an AGM battery system is about one-third that of a lithium equivalent. Additionally, there is a 10% payback on the scrap value when the battery reaches the end of its life. AGM batteries typically last between 4 to 10 years, depending on how well they are maintained and the frequency of their discharge. Using multiple batteries in a bank enhances performance, and these batteries come with an unlimited warranty for manufacturing defects.

Lithium:

Lithium batteries are considerably more expensive, though prices have decreased recently due to a flood of new products coming on to the market. Most lithium batteries now include a 12-year warranty, and their lifespan is considered to last longer than that, depending on the size.

 

CIRCULAR ECONOMY

Lead Acid:

AGM batteries contribute to a circular economy; even if not remade into new batteries, their components can be repurposed for other products, including smelting acid for glass production. Numerous facilities are available for battery recycling.

Lithium:

As noted earlier, lithium batteries do not participate in a circular economy, and there is no demand for such a system.

 

INSTALLATION

Lead Acid:

The installation process for AGM battery systems remains relatively straightforward. Adequate well-ventilated space must be allocated for housing the batteries, preferably outdoors near the battery management system. They are heavy to move though so once they are in their location is not the easiest to move.

Lithium:

Regulations on the installation of lithium batteries is rapidly changing due to their fire and other safety risks. There are now many restrictions for public buildings and insurance implications whereby many insurers won’t offer policies and cover where lithium is used.

 

Moving Location and Module Building

Lead Acid:

AGM batteries are very easy to move (although heavy) and modulate as each one can be used in a plug and play scenario. Whether it’s moving property or just moving the batteries within their current location, this can be done easily and safely by isolating the system and uninstalled each battery. Individual AGM batteries can also be removed and replaced within a system very easily and safely. You must conscious of the age of the existing batteries and their capacity if adding / replacing batteries.

 

Lithium:

Moving a lithium battery is a cumbersome process and in some installations, once they’re installed, they cannot be removed, only decommissioned at end of life. As lithium doesn’t allow you to work on a ‘cell by cell’ level, they are not modular in the same way as AGM. Once you have the battery in place, that is the capacity you have. Installation and removal must be done only be trained professionals and with the lithium battery in certain states of charge and condition. There are newer models now out which offer a modular option.

 

In Conclusion:

Lithium batteries offer clear advantages in terms of size, lifespan, and maintenance requirements, making them appear to be an obvious choice at first glance. However, when considering the goal of building a greener economy, one must question whether lithium batteries are the best option. Issues arise from their mining and production processes, often conducted unethically. The use of strong adhesives and the complex internal layout complicate recycling efforts, making it both impractical and costly. Each manufacturer designs their batteries differently, further hindering standard recycling practices. Furthermore, the risks associated with fire, explosions, and toxic vapor clouds are only beginning to be thoroughly investigated.

While AGM technology may be older, it presents a greener, viable alternative that has been overlooked. Its larger size and shorter lifespan may reduce its market appeal, but if a truly green solution is the aim, AGM batteries could be an excellent choice. Their initial costs are significantly lower than lithium batteries, they are fully recyclable, and offer a 10% payback on scrap value. AGM batteries are also portable, allowing for easy relocation if necessary, and can be configured to adjust the size of the system as needed. They exhibit a much lower risk factor, making them a safer option overall.

Previous
Previous

Spotlight on mobility. Classic Collection