Due to its safety and low price, lead-acid batteries are widely used and widely used. In different usage occasions, there are different usage requirements. In order to meet these requirements, various batteries with different structures are derived. When designing a circuit, choosing an appropriate battery structure will produce many benefits. This time, some commonly used structures are introduced, and some wrong structural designs are analyzed. For more battery knowledge, please visit Tycorun Battery to learn and discuss with us.
- Starter battery
A battery used in a motor vehicle to start the engine. This working condition requires that the battery can output a large power during the start-up process in a few seconds. The technical requirements of this type of battery are mainly output power.
In the formula P=1U, P is the power; I is the current; U is the continuous stable voltage when the output current I is, and I and U are symbiotic parameters. There is a low temperature requirement for the starting power P. The expression value for civilian use specifies the power supply characteristics at -18°C, and the military product requires testing at -40°C. Regulations vary slightly from country to country.
Starter batteries are commonly used in three types: 60Ah, 100Ah and 200Ah. 60Ah is used for cars and jeeps, 100Ah is used for medium-sized vehicles with an engine power of about 90kw, and 200Ah is used for diesel engines. and other large motor vehicles. The starting batteries are basically designed as a conjoined piece with a nominal voltage of 12V and cannot be disassembled for use. The connection between the cells of this kind of battery is inside, the appearance is neat, and there are only two output terminals, positive and negative. The plate structure of this kind of battery is flat. Short cycle life.
In many cases, circuit designers often use such batteries for photovoltaic power plants and electric vehicles, which is wrong.
- Energy storage battery
This type of battery is suitable for discharge at a rate of 10h or longer. The density of the electrolyte is low, usually around 1.24g/cm. This type of battery is mostly used for backup power supply, with a service life of more than 10 years, and some have been as long as 20 years. Energy storage batteries are also called stationary batteries.
- Power battery
The substrate structure of this type of battery is different from that of the starting battery, mainly because the positive electrode structure of the battery is a cylindrical tube. The cycle life of this type of battery is about 750 times, and the plate structure of the plate is only about 300 times. This type of battery is suitable for deep discharge and has obvious advantages when used in electric vehicles.
- Wrong combination of special structure batteries
Generally, the monomer capacity of lead-acid batteries is 500Ah, which is a large number in the market. When it is necessary to increase the capacity, the manufacturer often adopts the method of parallel connection to combine the single battery pack and supply it to the user. Figure 1 shows the combined structure of a 3000Ah large-capacity battery. Four single cells are installed in a conjoined plastic shell to form a single cell with a voltage of 2V. Then use 6 single cells in series to form a 12V battery string.
The advantage of such a combination is that it has a neat appearance, but the disadvantage is that the reliability is poor, and once one of the batteries is damaged, it is difficult to maintain. The mass of each battery is 230kg, which is difficult to transport and replace, and there are no spare batteries that can be replaced. Such a battery structure is made by the battery factory to meet the requirements of users. The root cause is the unreasonable requirements put forward by users, which is caused by lack of knowledge of batteries. The user is the buyer, and the battery factory lacks the right to speak. The communication industry has proposed a 24V conjoined battery and formulated a standard. The cost of using such a battery is several times higher than that of the series combination of monomers.
Read more: Four evolutions of lead-acid batteries