The difference between 3C and 10C for lithium ion batteries

If the battery capacity is 1Ah, 1C is 1A current, 3C is 3A current and 10C is 10A current. The battery capacity is different multiplied by the ratio!

Common cobalt acid lithium battery can discharge at most 3C, 10C basically only lithium iron battery can do. So the price of 10C discharge will be much higher, and the energy density will certainly be lower!

Lithium battery

Lithium battery is a lithium metal or lithium alloy as the cathode material, the use of non-aqueous electrolyte solution of the primary battery, and rechargeable battery lithium ion battery and lithium ion polymer battery is not the same.

The inventor of the lithium battery is Edison. Due to the lithium chemistry is very lively, making lithium metal processing, storage, use, very high demand on the environment.

So, the lithium battery has not been applied for a long time. As the end of the twentieth century the development of microelectronics technology, increasing miniaturization of equipment, puts forward high demands on the power supply.

Lithium battery then entered the large-scale practical stage.

The difference between lithium batteries and ordinary batteries

Lithium battery is a kind of lithium metal or lithium alloy anode materials, the use of water battery electrolyte solution.

The inventor of the lithium battery is Edison. Due to the chemical characteristics of lithium metal is very lively, so that lithium metal processing, preservation, use, environmental requirements are very strict. It is more environmentally friendly and convenient than ordinary batteries.

Basic knowledge of lithium ion battery: portable electronic products are powered by batteries. With the rapid development of portable products, the use of a variety of batteries, and the development of many new batteries. In addition to the more familiar high-performance alkaline batteries, rechargeable nickel-cadmium batteries, nickel-metal hydride batteries, there are lithium batteries developed in recent years. The basic knowledge about lithium battery is mainly introduced here. This includes its characteristics, main parameters, the significance of the model, the scope of application and matters needing attention. Lithium is a metal element, the chemical symbol is Li(its English name is lithium), is a silver white, very soft, chemical performance of the lively metal, in the metal is the lightest. In addition to its application in the atomic energy industry, it can be used to manufacture special alloys, special glass (fluorescent screen glass used in TV sets) and lithium batteries. It is used as the anode of a lithium battery.

Lithium batteries are also divided into two categories: non-rechargeable and rechargeable.

Non-rechargeable batteries as disposable batteries, It can only convert chemical energy into electrical energy once and for all, and cannot restore electrical energy to chemical energy (or very poor reduction performance).

Rechargeable batteries are called secondary batteries. It converts electrical energy into chemical energy and stores it, and when used it converts chemical energy into electrical energy and it's reversible.

The biggest characteristic of lithium battery is its high specific energy.

What is specific energy? Specific energy refers to energy per unit weight or volume. Specific energy is expressed in WH/kg or WH/L. WH is the unit of energy, W is watts, h is hours; Kilograms are kilograms, and L is liters.

Here is an example to illustrate: the rated voltage of no.5 nickel-cadmium battery is 1.2v, its capacity is 800mAh, and its energy is 0.96 WH (12V x 08Ah). A size 5 lithium-manganese dioxide battery of the same size has a rated voltage of 3V, a capacity of 1200mAh, the energy of 3.6wh. If the two batteries are of the same volume, the specific energy of lithium-manganese dioxide batteries is 3.75 times that of nickel-cadmium batteries. A nickel-cadmium no. 5 battery weighs about 23g, while a lithium-manganese dioxide no. 5 battery weighs about 18g. One lithium-manganese dioxide battery is 3V, while two nickel-cadmium batteries are 2.4v. Therefore, when lithium battery is used, the number of batteries is small (reducing the volume and weight of portable electronic products), and the working life of the battery is long.

In addition, lithium battery has the advantages of stable discharge voltage, wide operating temperature range, low self-discharge rate, long storage life, no memory effect and no pollution. The shortcoming of the lithium battery is expensive, so it is not widely used, mainly used in handheld computers, PDA, communications equipment, camera,special,special,special, instrument, etc. With the development of technology, process improvement and the increase of the production, the price of lithium battery will decrease continuously, applications will be more common. Non-rechargeable lithium battery non-rechargeable lithium battery there are a variety of lithium batteries, currently commonly used Li-manganese dioxide batteries, Li-thionyl chloride batteries and lithium and other compounds batteries. This paper only the most commonly used.

1 lithium - lithium manganese dioxide battery (LiMnO2) - manganese dioxide battery is a kind of anode for lithium, manganese dioxide as the cathode and uses the organic electrolyte of disposable batteries. The main characteristics of the battery is high battery voltage, rated voltage is 3 v general alkaline batteries (2 times); Terminate discharge voltage is 2 v. Larger than the energy (see the example above); Discharge voltage stable and reliable; Has good storage performance (more than 3 years storage time), low self-discharge rate, self-discharge rate of 2% or less (years); Working temperature range - 20 ℃ ~ + 60 ℃.

The battery can be made into the shape of the different ways to meet different requirements, it has a rectangular, cylindrical and button (button).The diameter of the cylinder also has different size and height. Rechargeable lithium ion battery rechargeable lithium ion battery is currently the most widely used in mobile phone battery, but it is "temperamental", in use do not overcharge, discharge (can damage the battery or scrap).As a result, have protection components or protection circuit on the battery to prevent damage of expensive battery. High demand for lithium ion batteries, to ensure the termination voltage precision is within 1%, the current major semiconductor device factory has developed a variety of lithium ion battery charging IC, to ensure safe, reliable and fast charging. Now mobile phone is very common that a part of the mobile phone is nickel metal hydride battery, but to poach mobile phone is lithium ion battery. Proper use of lithium ion battery is very important to extend battery life. Lithium ion battery is the most widely used lithium battery, it according to the requirements of different electronic products can be made flat rectangular, cylindrical, rectangular and button, and there are composed of several cells in series with the battery pack.

The lithium ion battery of the rated voltage of 3.6 V (some products of 3.7 V).Fully charged when the termination of charging voltage related to battery anode material: 4.2 V for graphite anode materials; Anode material for coke 4.1 V. Different internal resistance of the anode materials are also different, coke anode resistance slightly larger, its discharge curve also slightly different. It is generally known as 4.1v lithium ion battery and 4.2v lithium ion battery. Most of the current ones are 4.2v, and the termination discharge voltage of li-ion battery is 2.5v ~ 2.75v (the battery factory gives the working voltage range or the termination discharge voltage, each parameter is slightly different). Below terminate discharge voltage continue to discharge called discharge, discharge the battery will be damaged. Lithium ion battery is not suitable for used as large current discharge, large current discharge will reduce the discharge time (internal will produce high temperature and energy losses). Therefore, the maximum discharge current given by the battery production factory should be less than the maximum discharge current in use. Lithium ion battery has certain requirements on temperature that given by the factory, discharge temperature range and storage temperature range.

Lithium ion battery is very high to the requirement of charging, it requires that the precision of the charging circuit to ensure the safety of charging. Termination of charging voltage accuracy tolerance for rating plus or minus 1% (for example: 4.2 V lithium ion batteries, the tolerance is + / - 0.042 V), overvoltage rechargeable lithium-ion batteries, permanent damage. Lithium ion battery charging current should be on the advice of the battery factory, and ask the limited current circuit in order to avoid happened flow (overheating).Charge rate usually used is 0.25 C ~ 1 C (C is the capacity of the battery, such as C = 800mah, 1 C charge rate the charging current is 800 ma).Tend to detect when large current charging battery temperature, to prevent overheating damage to the battery or explosion.

Lithium ion batteries are divided into two stages: the first constant current charging, to about the termination voltage to constant voltage charging. This is 800mah capacity of the battery, the termination of the charging voltage of 4.2V.Battery at 800 ma (charge rate for 1 c) constant current charging, battery voltage with a larger slope booster at the beginning, when the battery voltage close to 4.2 V to 4.2 V constant voltage charging, gradual decline current, voltage change is not big, the charging current to 1/10 c (about 80 ma), close to full, may terminate charging (some charger to start the timer after 1/10 c, after a certain time end charging).Lithium-ion batteries in charging or discharging process if happened or over-current etc. To top it off, will cause damage to the battery or reduce the service life.

Application note: lithium ion battery application considerations in addition to the same as the above non-rechargeable lithium batteries, also in charge should be paid attention to the following:

1. Lithium ion battery has different types of 4.1v and 4.2v termination charging, so it is important to note that 4.1v battery cannot be charged with 4.2v charger, otherwise there will be the risk of overcharging (4.1v and 4.2v charger IC is different!).

2. The battery charging, the environment temperature cannot exceed product features the temperature range listed in the table.

3. Can't reverse charge.

4. Cannot use rechargeable nickel cadmium battery charger (three nickel cadmium battery charging for rechargeable lithium ion batteries (although the rated voltage, 3.6 V), but different charging ways, easy to cause the overcharge.

In terms of discharge should pay attention to the following points:

1. The lithium ion battery discharge current can't more than product features maximum discharge current is given in the table. When the discharge current is larger, can produce high temperature (energy loss), reduce the discharge time, unless otherwise stipulated in the battery protection components will cause overheating and damage to the battery.

2. Different temperature lowering electricity curve is different. It can be seen that under the different temperatures, the discharge voltage and discharge time is also different. In the worst - 20 ℃ discharge.

In the storage aspects:

1. If the battery is stored for a long time, it should be kept in 50% discharge state.

2. The battery should be stored in low temperature and dry environment.

3. Keep away from heat sources and from direct sunlight. Image of the working principle analogy: now lithium ion battery principle and charging and discharging mechanism, with a common phenomenon in life to analogy foam.

Lithium-ion batteries are like soap bubbles, in which energy is stored. When charging, the bubble will be increasing with charging time extended, the bubble will burst when over the limit, at this time it may damage the lithium electricity crystal type, causing permanent damage. Excessive discharge can cause bubble collapse and disappear, the next time the charging bubble cannot charge up and cause lithium electricity failure. How do you control the bubbles without charge blasting and bubble collapse? It must be strictly controlled by protective circuits. Of course, high quality cell and accurate control circuit can greatly extend the service life of the battery. Stationmaster likes to use lithium ion battery most because of its little self-discharge, large capacity and superior performance.

The page contains the contents of the machine translation.