polymer lithium battery

Lithium Polymer Battery

Lithium polymer batteries (also known as “Li-Po”) have gained attention in recent years because of their ability to safely and effectively power wearable devices. These batteries can be found in many different types of products, including electric vehicles, laptops, and even smart watches.

Their unique design uses a solid dry polymer electrolyte that resembles a plastic-like film, replacing the traditional porous separator that is soaked in lithium salt. These batteries also do not have a memory effect, and their cycle life is long.

1. High Energy Density

The higher the energy density, the more polymer lithium battery power a battery can deliver. This makes it essential to power the many devices that we use.

Researchers have recently developed a pouch-type lithium polymer battery that offers an incredible 700 Wh/kg. This is a substantial improvement over traditional lithium-ion batteries that typically only offer 30-40 Wh/kg.

They achieve this by replacing the porous separator with a solid, plastic-like film that allows the flow of ions but prevents leaking. They also have a new type of electrolyte that is liquid-free and uses a polymer binder (such as polyethylene or polypropylene).

Another advantage is that they are ultra-thin compared to other lithium batteries. This means that they can be made in a variety of shapes and sizes, which helps with the miniaturization needed for smart wearables. They can even be made as thin as a credit card! The thinness of the cell also makes it easier to design a protection circuit that can omit PTC and fuses, which can improve safety. Lithium polymer batteries are also less likely to swell as they heat up, unlike liquid cells that can explode.

2. Long Lifespan

Lithium polymer batteries are used in a variety of electronic devices. They are especially common in R/C drones and wearable electronics that need a battery with a long lifespan. These batteries are more expensive than standard lithium-ion batteries, but they have a much longer lifespan and higher energy capacity. However, they can still short-circuit if lithium dendrites build up between the positive and negative terminals of the battery.

The lifespan of a polymer lithium battery depends on various factors, such as temperature, charging patterns, and product power consumption. Manufacturers often estimate battery life in terms of charge cycles rather than a fixed number of months. In general, a lithium polymer battery can last 300 to 500 charge cycles before its capacity decreases significantly.

The lifespan of a lithium polymer battery can be greatly increased by restricting the depth of discharge (DoD). DoD refers to how far a battery is allowed to drain before it’s recharged. A shallow DoD will dramatically increase a battery’s cycle life. Other measures that can extend a battery’s lifespan include avoiding extreme temperatures and using original chargers.

3. Light Weight

The internal resistance of polymer lithium battery cells is smaller than that of ordinary liquid cells, which greatly reduces the self-consumption current and extends the standby time. They are especially suitable for portable electronics that need a lightweight power source, such as Bluetooth headsets and cordless sensors.

Lithium polymer batteries are much lighter than lithium-ion batteries and have a lower chance of leaking electrolyte (Li-ion has a high aging rate even when not in use). They can be formed into thin shapes to fit in stylish mobile phones, tablet computers, and wearables. They also don’t need a rigid case like Li-ion, which saves weight and space.

This is a very slim and lightweight LiPoly battery cell that outputs 3.7V at 120mAh. It comes terminated with a JST connector (2mm spacing between pins) that plugs directly into the Altus Metrum flight computer’s battery terminals.

4. Low Mold Opening Cost

Lithium polymer batteries are manufactured using battery injection moulding which essentially builds the cells into a geometric shape. Unlike conventional alkaline, NiCd, nickel-hydride or lead-acid batteries that have to be shaped by cutting, grinding or pressing them into place, polymer lithium batteries can be moulded into whatever size and shape required to accommodate them in the car. This allows weight balance to be more evenly distributed and improves overall performance, including the longevity of the battery pack.

Battery injection moulding uses pressure and heat to fusion, melt and blend the underlying polymer alloys into a solid mass. This ensures that there are no air bubbles, voids or gaps to compromise cell efficiency and safety.

The process is also more economical than current production methods, allowing the production of large format cells with conformal geometries for applications in a variety of cars. As a result, these batteries can be more evenly balanced and deliver the power and energy capacity that is promised on the label. This is crucial for long term performance and reliability. While li-po batteries have received some bad press lately due to a few high profile cases of them spontaneously catching fire, they are still an excellent choice for electric vehicles as long as you take care of them correctly.

5. High Safety

Lithium polymer batteries are much more compact and lighter than lithium-ion batteries, making them Solar energy storage system perfect for powering slim devices like smart wearables and electronics. They are also more reliable than liquid batteries because they won’t explode or swell under pressure, but they can overheat if the internal temperature rises too high.

The key to avoiding this problem is to properly care for your Li-Po cells and avoid exposing them to extreme temperatures or environments, where they could overheat and start a chemical reaction that leads to fire. This is why it’s important to keep them in a cool and dry place like your ESC or charger case when you are not using them, and to store them in a plastic bag with a little bit of dry sand for extra protection.

Another safety feature of these batteries is the solid electrolyte. Unlike the liquid electrolyte of traditional lithium batteries, which can decompose and burn under certain conditions, the polymer electrolyte used in polymer lithium batteries has good processability and high safety. However, the emergence of lithium dendrites on the surface of the negative electrode and battery thermal runaway still remain as concerns for polymer solid-state batteries.