The Dangers of a Li-Ion Battery Pack
You’ve likely used lithium batteries before, from a toothbrush or power tool to a laptop or cell phone. But did you know that these battery technologies can be very dangerous?
Lithium batteries power many industries, including the back-up power needed for office equipment and data storage or to ensure consistent power supply to lifesaving medical equipment. They also offer a number of distinct advantages.
Energy Density
The energy density of a battery is the amount of power it can hold in a certain volume. This is the most important factor for EVs, because it determines how long the car can travel on a single charge.
Li-ion batteries have the highest energy density of all rechargeable battery technologies. This allows them to be smaller and lighter than other types of batteries without sacrificing power capacity. This enables new, compact consumer electronics, such as smartphones and laptops. It also makes it Li-ion battery pack possible for EVs to travel further on a single charge than traditional gasoline-powered cars.
Batteries work by storing energy in positive and negative electrodes. During use, electricity flows from the positive to the negative electrodes. As the lithium ions move in and out of the electrodes, they create a voltage that increases with increasing current. The amount of energy stored in the battery is equal to the voltage times the charge.
A typical Li-ion battery cell has a graphite negative electrode, and a metallic or ceramic positive electrode with a lithium salt in an electrolyte. Graphite is the most common negative electrode material because it has a low intercalation voltage and offers high performance. Other materials such as nickel-cobalt-manganese oxide have been used, but they offer lower capacity and performance.
Our team is continuously working on improving the technology behind lithium-ion batteries, so they can be even better than they are today. Our goal is to increase their efficiency and reduce costs, so they can be available to the masses in a shorter time.
Long Lifespan
Lithium ion batteries are used in many of the portable electronic devices that we use today. These include laptops, tablets, cordless drills and even Tesla’s electric vehicles. They have a much longer lifespan than their NiCad and NiMH counterparts. This is mainly due to the fact that Li-ion batteries self-discharge at an imperceptibly slow rate.
They also have a lot more technology at work in them than NiCads did, meaning they’re less susceptible to battery degradation and other problems that can shorten their lifespan. For instance, most Li-ion batteries have overcharge, overdischarge and overheating protection built in. This protects the battery from damage and extends its expected cycle life.
When storing lithium batteries, it’s important to keep them at about 50% charge or the level recommended by the manufacturer. You should also store them in a cool area, as heat is lithium’s worst enemy.
It’s important to note that battery manufacturers refer to the lifespan of their batteries as a function of charging patterns, rather than an expiration date. This is because waiting for extended periods between charging cycles will negatively impact the battery’s lifespan. In general, a Li-ion battery will lose 20% of its usable capacity over the course of 1,000 cycles. This is a significant amount, and it’s one of the reasons why you should only purchase and use genuine manufacturer batteries and chargers.
Lightweight
As lithium-ion batteries are rechargeable, they require less maintenance than other battery types such as nickel-cadmium or nickel-metal hydride. Additionally, they don’t suffer from memory effect – a detrimental phenomenon whereby repeated partial discharges and charges cause the battery to “remember” a lower capacity. This is why they are so popular for use in power tools.
Lithium-ion batteries are also lightweight, which makes them ideal for wearable devices that need to be portable and versatile. Their thin design offers a large amount of energy storage in a small space and they can be powered for long periods of time, even while being bent repeatedly at radii of curvature of up to 1 mm.
Rigid-type lithium-ion batteries fabricated on metallic foils currently dominate battery technologies for portable electronics due to their relatively high energy density and excellent cycle life. However, the need for lightweight and flexible energy storage units with high areal capacity and cycling stability is pressing4,5,6,7.
Lithium-ion batteries can have a negative impact on people and the planet, because the raw materials needed to produce them are extracted from the earth in unsustainable ways. It is essential that governments and industry leaders find a way to mitigate these negative impacts, particularly as the demand for lithium rises. To do this, they must move from recycling to reuse of the metals used to make lithium-ion batteries.
Rechargeable
The rechargeability of Li-ion batteries allows them to be used many times, reducing product replacement costs. Additionally, they are environmentally friendly since they avoid Li-ion battery pack the need to throw away and recycle traditional batteries.
The chemistry behind lithium-ion battery packs is more advanced than other rechargeable battery chemistries, such as nickel-metal hydride, which makes them ideal for cordless and portable consumer electronics. This enables manufacturers to build smaller, lighter devices using less battery volume.
Like other rechargeable batteries, a lithium-ion battery pack has defined positive and negative sides that switch when the battery is charged or discharged. When the battery is being used, it is part of a closed circuit (i.e. the device it is powering is in operation). As it discharges, the cell’s SEI thickens, robbing the anode of its available lithium ions to reduce its cycling capacity and stability.
When the battery is charging, a transistor circuitry controls the charge current, stopping it once the battery has reached its top-of-charge voltage limit per cell. This is known as balancing and may take hours or days to complete.
Because they contain flammable electrolytes, Li-ion batteries require careful engineering and design to ensure safety. They must be shipped in accordance with strict domestic and international regulations. These regulations apply to both shipments by land, sea and air.