Generally, adhesive-backed Qingke paper (fish paper/insulating paper) is used for insulation, with a thickness of about 0.25 mm.
Lithium Battery Production Equipment
There is a great deal of lithium battery production equipment. In terms of major processes, lithium batteries involve, first, producing lithium battery cells, and second, packaging the cells into finished lithium batteries (also called PACKs). If you are doing the second, you can consider purchasing lithium battery cells and then processing them into finished lithium batteries, which requires less investment. If you are making lithium battery cells, there are many processes. Starting from raw material procurement, they are divided into major processes such as slurry mixing – coating – baking – slitting – electrode preparation – winding – inserting into the case – electrolyte injection – sealing – formation, and the investment is very large.
The main automated assembly equipment and procedures for lithium battery packs (PACKs) are as follows:
In the battery industry, what does PACK mean? Do these four letters stand for something separately? Thank you!
PACK generally refers to an assembled battery. A PACK can be a single battery, such as a mobile phone battery, digital camera battery, MP3/MP4 battery, etc., or a series-parallel combined battery, such as a laptop battery, medical device battery, communication power supply, electric vehicle battery, backup power supply, etc.
Batteries connected in parallel and series are required to be of the same type and model, with differences in capacity, internal resistance, and voltage not greater than 2%. In essence, this is consistency of the battery charge/discharge curves (dynamic consistency). However, this is difficult to achieve. Generally, after batteries are combined in parallel and series, the capacity loss is 2%–5%; the more batteries, the greater the capacity loss.
- Overcharge protection. Different battery systems have different overcharge protection voltages. Generally, for lithium iron phosphate, the overcharge protection voltage is 3.65 V–3.85 V; for lithium cobalt oxide, lithium manganese oxide, and ternary-material lithium batteries, the overcharge protection voltage is 4.2 V–4.35 V.
- Over-discharge protection. The over-discharge protection voltage of lithium iron phosphate is 2–2.5 V; that of the other three types of lithium batteries is 2.3 V–2.9 V.
- Short-circuit protection. This is determined by the parameters of the IC and MOSFET. Different ICs and MOSFETs have different short-circuit protection values.
- Overcharge protection recovery voltage. ICs all have this function; generally, the recovery voltage is 0.1–0.2 V lower than the protection voltage.
- Over-discharge protection recovery voltage. Some ICs do not have this function. After over-discharge, the battery needs to be restored by charging.
- Short-circuit protection delay time. Generally, this is a dozen milliseconds or so.
- Balancing function. Some applications require a balancing function. Because the battery discharge current is relatively large, balancing is not easy to achieve. At present, charging balancing is mostly used. The purpose of balancing is to ensure that each battery can be fully charged, extend service life, and maximize battery performance.
