Which is safer between lithium batteries and lead-acid batteries?

Lithium battery or lead-acid battery, which is safer? From the perspective of battery safety protection, safety valves are designed on the 18650 batteries, which can not only release excessive internal pressure, but also physically disconnect the circuit between the battery and the outside world. Connection is equivalent to physically isolating the battery cell to ensure the safety of other batteries in the battery pack. In addition, lithium battery packs are usually equipped with a BMS protection board, which can accurately control the state of each cell in the battery pack, and directly deal with the problem of overcharge and overdischarge from the root cause. Lithium battery BMS battery management system can provide full protection to the battery. The functions include: charge/discharge high and low temperature protection; single cell overcharge/overdischarge voltage protection; charge/discharge overcurrent protection; cell balance; short circuit protection; Recharge reminders and so on. The electrolyte of the lithium battery pack is a mixed solution of lithium salt and organic solvent. The commercial lithium salt is lithium hexafluorophosphate. This material is prone to thermal analysis at high temperatures and undergoes thermochemical reactions with trace amounts of water and organic solvents to reduce The thermal stability of the electrolyte. Power lithium batteries use lithium iron phosphate. The PO bond in the lithium iron phosphate crystal is stable and difficult to analyze. Even at high temperatures or overcharge, it will not collapse and generate heat or form strong oxidizing substances in the same structure as lithium cobalt oxide. Good security. A report pointed out that in actual operation, a small part of samples were found to burn in acupuncture or short circuit test, but there was no explosion. The safety of lithium battery packs has been greatly improved. On the contrary, lead-acid batteries lack BMS system protection. Lead-acid batteries seem to be lacklustre except for safety valves in terms of safety protection. BMS protection is almost non-existent. Many low-quality chargers can't even cut off power after overflow. Safety protection is far from lithium batteries. Coupled with inferior chargers, your character is good if you don't have an accident. Spontaneous combustion and explosion of electric vehicles often occur, most of which are caused by battery charging and discharging. Experts explain that the charging time of lead-acid batteries is too long. After charging to the end, after the two poles are converted into effective substances, if the charging is continued, a large amount Of hydrogen and oxygen gas. When the concentration of this mixed gas is 4% in the air, it is too late to escape. If the vent is blocked or there is too much gas, it will explode when encountering an open flame, which may damage the battery in the slightest, and injure people and objects in the severe case. That is, once the lead-acid battery is overcharged, it will increase the probability of explosion. However, the lead-acid batteries currently on the market do not have any overcharge protection, which makes the lead-acid batteries during charging, especially the lead-acid batteries at the end of charging, extremely dangerous. Finally, if the battery structure is damaged due to an accidental collision, lead-acid batteries seem to be safer than lithium batteries. However, in this level of accident, the battery material has already been exposed to the open environment, and there is no way to talk about explosion. Disclaimer: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact to delete it. Previous: Is the Tesla Power Lithium Battery Explosive?