The charging methods of lithium-ion batteries and lead-acid batteries are different.
Lead-acid batteries are durable and have low requirements for charging circuits. A 12V lead-acid battery can be charged with a voltage not exceeding 15V.
And the current is not particularly large. Occasional overcharging and overdischarging will not cause battery damage.
Do not protect the circuit, the structure of the charger is also very simple, basically it is a DC power supply.
Therefore, a circuit with constant voltage (14.5V) current limiting (0.1-0.4C) can charge lead-acid batteries.
Lithium-ion batteries are more delicate, and overcharging and overdischarging can cause immediate damage to the battery.
Therefore, almost all lithium-ion batteries are equipped with protection circuits, which are packaged with lithium-ion batteries.
Although it is equipped with a protection circuit, the lithium-ion battery still needs constant current charging, and when the voltage rises to 4.2V (trickle charging threshold), it will switch to constant voltage charging
What is the difference between lithium-ion batteries and lead-acid batteries?
1 The charger adapted to the lithium-ion battery implements constant current and constant voltage. Because the internal resistance of the lithium battery is small, the constant current is first ensured in the design of the charger. No matter how low the lithium battery is, it can only be charged. The output is nominal (such as 1A), which is the limit of constant current. The special feature of this mobile phone charger is to ensure that the voltage is higher than 4.2v when ensuring constant current, and no current can be formed if it is too low.
During charging, the current of the lithium battery will gradually decrease with the gradual increase of the power, and the voltage will gradually rise, and it will automatically cut off when it finally reaches the standard 4.2v.
Because lithium batteries are relatively delicate, we must pay attention to the technical content of the protection board. It is not allowed to be careless. If it exceeds 1% and continues to charge upwards, there will be accidents such as bulging. Therefore, the charger should be adapted to the original factory, and the charger should not be used indiscriminately.
2 Lead-acid batteries are not as expensive as lithium batteries. For example, you can use a transformer to charge a diode half-wave rectifier, but this is not recommended. Electric vehicles are equipped with suitable chargers, which can be charged by pulse, and can be charged in three-stage, constant current and constant voltage trickle charging.
Why pay attention to 30% of the power to charge upwards, when the battery is low, the constant current and full load will be transferred. At this time, the heat generated by the plate is the largest, which will cause the lead powder of the plate to fall off, which will make the battery cruising range shorter and shorter.
In fact, lead battery chargers are also similar to lithium battery chargers. When charging, each 12V battery can be assigned a voltage of 14.5V, which not only ensures constant current but also ensures sufficient voltage. When the box cools down, the current stops.