The difference between liquid lithium battery and polymer lithium battery

by:CTECHi     2021-07-30

Everyone hears a lot of lithium batteries for mobile phones, but how are these things classified? (Lithium-ion battery is abbreviated as lithium battery below) In fact, in the field of electronic products, lithium batteries are commonly used in liquid lithium-ion batteries and polymer lithium-ion* (18650 refers to a cylindrical battery with a diameter of 18mm and a length of 65mm. Although most of the 18650 on the market are liquid lithium batteries, any statement that 'polymer lithium batteries are safer than 18650 XX' is wrong.) What is the difference between them? First of all, it needs to be explained that the working principle of the two is the same. Both charge and discharge are realized through the process of lithium ion insertion and extraction. The insertion of lithium ions into the negative electrode is charging, and the extraction of lithium ions from the negative electrode is discharge. Mobile phone lithium battery tips: you have to look at the picture above. We can see that the lithium battery contains the three most basic elements of positive electrode, negative electrode and electrolyte (the substance filled between the two levels). Of course, there is also prevention in the middle. The positive and negative electrodes are in direct contact with the separator (of course, lithium ions can pass smoothly, if the separator is not good, it will cause an explosion~~). The main difference between liquid lithium ion batteries and polymer lithium ion batteries is 1. Material The above difference: In polymer lithium batteries, at least one of the above three basic elements must be made of polymer materials, for example, the electrolyte solution is replaced with polyacrylic acid, polymethacrylic acid and other weird things. 2. The difference in electrolyte morphology: liquid lithium-ion batteries mostly use liquid organic solvents + conductive salts, while polymer lithium batteries replace these electrolytes with gels/solids (see the battery model for specific components). What's so awesome about each of them? Simple comparison of polymer lithium battery/liquid lithium battery Energy density of liquid lithium battery (Wh/L)>300200~280 Customizable degree (shape) flexible and difficult light weight (no metal protective shell required) heavy (metal protective shell required) safe Sexual safety is more expensive and cheaper than safety. 1. Energy density: The greater the energy density, the more capacity a unit volume can have. The energy density of the polymer lithium battery has now reached 600Wh/L+ through the improvement of materials/thickness of the negative electrode (anode) and separator. 2. Degree of customization: The polymer lithium battery is easier to be thinner in shape, and there is no need to use a metal protective shell to wrap it, so it is easier to customize into various shapes. 3. Weight: It has been indicated on the form. 4. Safety: Under extreme conditions (such as overcharge/high temperature), a violent chemical reaction will occur inside the lithium battery, which will produce a large amount of gas. At this time, the liquid lithium battery is wrapped by a metal shell, and the shell will be affected when the internal pressure is quite large. A rupture and explosion occurs, and because the polymer lithium battery is only wrapped with packaging aluminum film (or plastic shell), as long as the internal pressure is slightly higher, it will expand or rupture, and will not cause an explosion. However, it should be noted that both liquid lithium batteries and polymer lithium batteries can burn under extreme conditions. 5. Cost: In addition to the higher material cost of polymer lithium batteries than liquid lithium batteries, because polymer lithium batteries can be customized to a higher degree, more costs will be incurred in the design and manufacturing process, such as various customized Tooling fixtures, test equipment, etc., cause the cost of polymer lithium batteries to be higher than that of liquid lithium batteries with standard/regular shapes. How to distinguish whether the mobile phone is a liquid lithium battery or a polymer lithium battery? For the sake of lightness and capacity, current mobile phones use polymer lithium-ion batteries. Whether it is a soft case like the iPhone or a plastic hard case like the previous Nokia, it is a polymer lithium-ion battery. Tips on mobile phone lithium battery: Before you fry, you have to see where you can find a liquid lithium-ion battery? Take apart your heavy and thick laptop battery at home, or take apart your dad’s large toy car (Tesla). How can it be safe to use a polymer lithium battery (mobile phone)? In fact, how to protect the polymer lithium battery is relatively simple, we just need not to put the mobile phone in high temperature, high humidity, and avoid using it in the environment of sun exposure. In addition, do not overcharge and overdischarge lithium batteries. Because the polymer lithium battery cells in the mobile phone are protected by a protective plate, they will automatically cut off after being fully charged, so there is no danger of overcharging (if the protective plate is broken), use the mobile phone. It is best not to fully use up the battery before charging, otherwise it is easy to damage the active material at the two poles of the battery and cause the battery capacity to decrease significantly. Tips on mobile phone lithium battery: Before you fry, you have to see how to activate the newly purchased lithium polymer battery (mobile phone)? The new polymer lithium battery (mobile phone) can be activated by normal charging and discharging 3~5 times, without charging for 12 hours, because the polymer lithium battery does not have a memory effect, and the saying that 'new mobile phones need to be charged for 12 hours' is only true Ni-Cd and Ni-MH batteries are effective. Besides, it is protected by the protection board. The charging circuit will be disconnected after full charge. If you plug in the charger, it will be in vain, and the electric energy will not reach the battery. The polymer lithium battery is not used for a long time (the mobile phone is idle for a long time), how to protect it? If the lithium battery (mobile phone) is not used for a long time, it is best to reserve about 50% of the battery's capacity to avoid the low voltage caused by the self-discharge of the lithium battery, which destroys the active materials of the two poles and causes capacity loss. In addition, it should be placed in a dry, cool place, because the self-discharge speed of lithium batteries will be faster in a high temperature and high humidity environment. When you take it out again, charge and discharge normally 3~5 times and reactivate it.

Custom message
Chat Online 编辑模式下无法使用
Chat Online inputting...