Which is better, 18650 battery or polymer lithium battery?

The so-called polymer lithium battery refers to using the polymer as the electrolyte lithium ion batteries. Specifically, it is divided into "all polymer" and "half polymer" two categories. "Half polymer" refers to coating layer of polymer (PVDF) on the isolation membrane, which makes batteries bonding strength is stronger, so that the battery can do much more rigid. The electrolyte is still liquid electrolyte. And "all polymer" refers to that the use of polymer gel network is formed within the cell, and then injected into the electrolyte. While "all polymer" will still use liquid electrolyte battery, but it has less dosage. The safety performance of lithium-ion batteries have greatly improved. Now only SONY produces "all polymer" lithium ion batteries.

On the other hand, polymer battery refers to the use of aluminum-plastic packaging film packaging of lithium ion battery, which is commonly known as soft package battery. This kind of packaging film consists of three layers, namely, PP, Al layer and nylon layer, because PP and nylon is a polymer, so this kind of batteries is known as the polymer battery.

1, the price is lower

18650 of the international price around 1 usd/PCS, according to the 2 Ah to calculate words is about 3 RMB/Ah. And polymer lithium electricity price and low-end fortress factory in 4 RMB/Ah, in the end in 5 ~ 7 RMB/Ah, high end over 7 RMB/Ah. Such as ATL, Lishen, generally can sell for around 10 RMB/Ah, and single small family also don't want to meet you.

2, do not order

SONY has been trying to made like alkaline batteries, lithium ion batteries have a certain industry standard, like 5 batteries, batteries, basically the same all over the world. But because of the big advantage is the lithium ion battery can according to customer demand for design, could not have a unified standard, so until now lithium-ion battery industry basically only 18650 this a standard model, the other is design according to customer requirements.

3, poor security

We know that the lithium ion battery in extreme circumstances (such as overcharge, high temperature, etc.), severe chemical reactions that can occur within the gas.18650 battery using the metal shell, there is a certain strength, when the internal pressure reaches a certain steel shell explosion will burst, very terrorist safe accidents.

This is why 18650 battery test room usually have to use layers of protection, and must not be in when you test. Polymer battery don't have this problem, even though in extreme cases, the same due to the low strength of packaging film, as long as the pressure slightly gao will burst, won't produce explosion, most of the bad situation is burning. So from the security polymer battery is better than 18650 batteries.

4, low energy density

General 18650 around 2200 mAh battery capacity can be done, so calculate down energy density about 500 wh/L, and the energy density of the polymer battery production at present stage can be close to 600 wh/L.

But polymer battery has its own shortcomings. Mainly the high cost, because can according to customer demand design, here the research and development costs into account. And changeful shape, phyletic and various, cause in the process of manufacturing all kinds of jigs and fixtures are standard parts, and the corresponding increase the cost. Poor universality of polymer battery itself, which is brought by the flexible design, often to 1 mm difference will need to design for the customer.

3, 18650, the application of lithium-ion batteries

Applications in lithium secondary battery energy battery industry due to its superior performance. With the development of lithium secondary battery technology has been widely used in our daily life; Repeat use of rechargeable batteries is more and more get the favour of consumers. Focus on energy battery industry, fully recognize the battery, in turn, let's do it "forms", currently 18650 lithium batteries have certain application in the field below.

1, energy storage

Mainly applied to the base station power supply, clean energy, energy storage, grid power energy storage, domestic optical storage system, etc.

2, power class

Mainly refers to electric vehicles, electric bicycle, new energy vehicles, etc.

3, digital

Mobile phone, tablet, notebook computers, electric toys, MP3 / MP4, headphones, charging treasure, model aircraft, mobile power supply, etc.

1, 18650 battery is cylindrical, internal liquid, because battery design and materials, 18650 is suitable for high current, so almost all notebooks are designed with 18650 batteries, electric vehicles; Only super notebook, because energy saving, so cannot use 18650 batteries and instead to use lithium polymer battery, especially tablets, etc.; Digital camera flash for charging and discharging need big voltage and instantaneous electric current, so can only use 18650 similar battery, the volume is a little small;

2 advantages, polymer lithium battery, small size, large capacity, the disadvantage is that life is shorter than the 18650, because of using different design and material, some internal liquid, some are dry or is colloid, and large current discharge performance is better than 18650 cylindrical battery, so I need the large capacity electric equipment of small volume, often use lithium polymer batteries, the most typical is the performance of the mobile phone, tablets and other devices.

The page contains the contents of the machine translation.