This is a lithium-Ion battery storage story. You probably know a thing or two about the use of batteries for solar storage, maybe even about the lithium-ion battery.
The newest trend in the production of clean energy implies replacing the Lead Acid battery with the lithium-ion battery for solar storage. The later one has turned out to be more effective than its once all-mighty competitor.
These Lithium-ion battery types of energy accumulators were invented in 1970. They did not take the market straight away because they needed improvement. In 1985, Japanese manufacturers showed the world an enhanced product, which was released six years later.
Initially, it was used for boosting the functioning ability of mobile phones and laptops. Soon, manufacturers become aware of its potential and started to produce larger cells with application in the electricity industry.
Process That Gives Life To A Lithium-Ion Battery
The Parts Of A Solar Generating System
Unlike their simple AA battery counterparts, the AA lithium ion battery are rechargeable. Li-Ion pile up power using lithium ion battery chemistry. This means their reagents can be regenerated if electricity passes through the inside. The empty battery is connected to a charger, which uses electricity to reverse the initial chemical reactions.
All lithium-ion batteries, including the ones employed for solar energy stocks, have two electrodes: a positive one made of a lithium compound and a negative one made of carbon. They are connected through an electrolyte, which allows the ions to move between the electrodes.
After discharge, the ions move from the carbon electrode towards the lithium one. The situation is inverted during the recharge process. Unfortunately, this back and forth process cannot last forever. In time, the electrodes swell and shrink.
Imagine your favorite clothes gradually losing their shape and wear out as you use them and wash them. Eventually, they cease to fit you perfectly. Similarly, the ions no longer match with the structure of the electrodes.
Lithium-Ion Battery For Solar Power Storage
Lithium is the lightest metal and therefore and it has the highest electrochemical potential. As a consequence, it has a superior electrical density. At the same time, it is a very reactive element, which means it can store huge amounts of energy. These qualities attracted the attention of innovative researchers who wanted an alternative to the lead-acid accumulators.
The LI-IONs are widespread nowadays. You find them on the market in three different formats:
The last ones have corrugated sides and the adjacent cells separated by air gaps. These two combined elements boost the cooling process.
The batteries were designed to hold the surplus electricity produced photovoltaic panels. The solar panels function while the sun shines outside. So, at the end of the day, you have lots of generated power. There are three options:
To store the excess electricity is a prudent choice.
Plus, using stored power later reduces your electricity bill. There may be weeks when your solar panel electricity-generating device may not cover the electricity demands of your household. In those periods the stored battery power can assist in providing some capacity.
If you want to get off the grid then it is paramount to purchase batteries and the lithium-ion battery for storage is an efficient choice.
Where Is Lithium-ion Battery For Storage Used?
Until recently, all independent systems, which generate electricity, have functioned on lead-acid accumulators. The advancement of technology and reducing cost of Lithium-Ion battery has lead to their increasingly being the replacement option for lead acid with their more effective alternative.
You can find banks of battery storage in residences that have solar panels on their roof. Commercial scale battery banks store energy in multi-megawatt containers, which supply the grid.
How Does Lithium-Ion Work In The Solar Home?
Briefly, solar power is directed from the panels and charge controller towards the bank of batteries. In most residential situations they are secured onto the interior (or exterior) wall. The process continues while the sun shines until the battery bank is charged. If you turn on the appliances in your house, electricity is drawn in the form of direct current (DC) from the battery. You need an inverter to transform DC into alternating current (AC) as most household appliances use AC power.
Why Are LI-ION Batteries So Popular?
In private residences that use solar batteries you will encounter one of the following battery devices:
The majority of new battery bank installations in residential properties with solar select the Lithium-Ion battery because they have a long lifespan (which varies between 13 and 18 years). Lithium-Ion battery tends to be lighter. Li-Ion has an increased DoD (Depth of Discharge) and good resiliency.
The lead-acid battery technology has been around for a long time. Their strong point is they have lower price per Amp/hour. They are heavy, have less DoD capacity so can last for shorter periods of time if discharged too far too many times.
Saltwater accumulators have been launched recently. They cost less and have a superior DoD when compared to LI-IONs. Their lifecycle has lower values. In addition, they are still very “green” and little tested. Producers need to collect more data to ensure authorities and buyers that the investment is a safe one.
Some Australian universities are looking at salt water and lithium Ion combination batteries.
What Effect Does The Lithium-Ion Battery Have On The Environment?
For people concerned about our impact on the environment, the use of batteries is a vexed one.
Their production process demands huge quantities of raw materials.
Whether it is lead, sulfuric acid, lithium, vanadium or cadmium, they all need to be resourced from the earth mines. When the batteries are at end of life few are considered economically recyclable. Thus, mines get deeper and air around the factories producing them becomes polluted.
The energy efficiency, expected economic life of the battery and the amount of raw materials used mean judgements are made about the environmental impacts of storage.
The lithium-ion battery puts less pressure on the environment because they need fewer raw materials, are efficient and have a long life. The nickel-cadmium batteries resist extreme weather conditions and some designs can function up to 20 years. But Cadmium is an unpredictable material and it’s a poisonous metal if utilisation afterwards is not controlled.
What Are The Advantages And Benefits?
Their features are generally economic as a result of continuous efforts to enhance the product.
1. Extensive Life Cycle
The number of times a battery can be discharged until total exhaustion represents its life cycle. When it comes to this aspect, the Lithium-Ion battery has between 4,000 and 6,000 cycles. However, Lithium batteries suffer from earlier ageing if worked or left in hot conditions.
They are chosen for ancillary battery storage services to Utility electrical grids. Lithium-Ion battery will charge and discharge (80% to 90%) on a regular basis. This allows them to gather more energy. When inactive, their capacity does not lag behind.
2. Easy Maintenance
You need to pay attention to maintenance schedules to ensure that a flooded Lead Acid battery functions well.
It demands systematic control of fluid level by checking battery electrolytes acidity levels correct.
Correct ventilation is required for most batteries but particularly Lead Acid flooded type. If ventilation is poorly done, hydrogen and sulfuric acid gases accumulate, increasing the potential for explosion and damaging the device.
If you fail to do the maintenance checks regularly, you may incur expensive repair costs. In the case where damage occurs you may have to buy another battery bank earlier than you had planned.
An advantage of lithium-ion battery for solar storage is they are less troublesome. These fully contained batteries require little to almost zero maintenance supervision. This is due to an integrated system, which adjusts the voltage and the temperature of every single cell.
The higher initial capital cost for lithium-ion battery storage is offset to some degree by lower maintenance requirements and efficiency.
3. Prime Capacity
A common LI-ION battery stores 1500Wh/kilogram. The nickel–metal hydride battery (abbreviated Ni-MH) stores 1000Wh/kilogram. The lead-acid battery stores 250 Wh/kilogram. Vanadium flow batteries have specific energies in the range of 10-20Wh/kilogram.
In other words, the lithium-ion battery technology is 6 times more efficient than a lead-acid battery. It is around 100 times more efficient than a vanadium flow battery. This difference is significant.
4. Reduced Size and Weight of Batteries
The LI-IONs battery weighs three times less than the Lead Acid battery, while their volume is halved.
Consider these as economic strengths because they have a positive influence on the shipping, installation and charging costs.
Also, the Lithium-Ion battery occupies less space per 1000Wh of energy storage. When room is tight that is an advantage.
5. Peace of Mind
A great benefit of this technology is high reliability and low maintenance in all weather conditions. In the periods of power outages you will continue watching your favorite movie series while your neighbors are searching draws for their torches.
Are There Disadvantages?
The Lithium-ion battery has a down side, or contras, so we will take a look and make that assessment in comparison with their upside potential.
Most people looking at a Lithium-Ion battery are dissatisfied with:
1. Lithium-Ion Battery Price
The Lithium-Ion Battery cost about double that of the Lead Acid batteries.
Yes, the initial price is higher, however, their long life, Depth of Discharge (DoD), fast charge technology and light weight helps investors save money over the long run.
2. Recycling Methods
These types of storage products contain either organic cells, which do not have harmful substances. Or, they have inorganic cells, which are toxic and you must be cautious about how and where you dispose them.
The current battery recycling procedure is expensive. Both used and virgin materials need to go through the same production operations. Therefore, manufacturers prefer to enrich the lithium at mines than be involved in lithium recovery methods. See this article that speaks about mining engineers who found new ways to make Li-ion battery recycling more cost effective.
3. High Temperature Sensitivity
Take care when charging lithium-ion batteries as they require protection from being overcharged and discharged too far. They are sensitive to high temperatures and heat will cause degradation of Li-ion batteries.
3. Transport Sensitivity
A lithium-ion battery is sensitive to high temperatures and can even explode when overheated, so airlines limit the number of Li-ion batteries a passenger may carry.
The Cost Of Lithium-Ion Storage
The aspect of pricing is influenced by the brand you choose to install. Manufacturers like Tesla, LG Chemical, Lithionics and Mercedes-Benz all try to take the lead, each having its own Lithium-Ion battery and price/kWh.
Assembling the panels and the battery at the same time is more cost efficient than retrofit options. You can easily attach the accumulator package to a pre-installed solar array. But, you will have added costs to get out electrical service type persons in addition to the battery bank investment sum of around $3000 to $5000 for an average home.
The prices for complete installations that include hardware wiring and brackets, panels, battery bank and labor range between $10,000 and $15,000. The sum includes installation fees and other items like inverters, safety switches and regulators.
To promote usage of clean electricity, most governments have some incentives. In the US the federal government covers 30% of the costs through the Investment Tax Credit. But, to qualify you must use solar energy, not electrical grid energy, for battery recharge.
The residents of California can apply for the Self-Generation Incentive Program. They can receive financial support to buy sun-powered gear.
The price for solar renewable electricity equipment and storage has come down over recent years. You can purchase a complete solar system product at a fraction of what it was ten years ago and these are not only more efficient, reliable and compact they have long warranties.
The Future Of Lithium-Ion Battery
The analysts have forecasted that by 2019, the price for the Lithium-Ion Battery will fall to $200/kWh. This reduction alone will make them the first choice for micro-grids and residential units.
By 2025, the US storage market will dominate, with a 21% increase in compound annual growth rate (CAGR). It will be followed by Australia and Japan.
It is expected that by 2030, the installation costs for complete solar systems with battery support will fall 60% as a result of technological development.
It is likely the lithium-ion battery with solar storage will become an automatic inclusion of planning most autonomous solar systems. It won’t just be a case of it being a viable solution for lighting the later hours of the night. It will be the most cost effective option for electrical generation.
References:
Source for Picture Lead Acid vs Lithium-Ion Battery
https://www.goendlessenergy.com/single-post/2016/07/25/Batteries-OffGrid-Storage-1
Source for Power Vault Diagram
http://www.isoenergy.co.uk/battery-storage-for-solar-panels
Source Size+Weight
http://www.iflscience.com/technology/tomorrow-s-battery-technologies-could-power-your-home/
I use Goal Zero lithium ion batteries. I think they are great. One pretty significant disadvantage of this technology you missed is they will not charge at low temperatures like less than 32F. My outdoor batteries are kept in coolers, with a small heat source, to get around this problem.