Effect of lead-acid charger on lithium battery charging
Effect of lead-acid charger on lithium battery charging
It's a little dangerous. It's not generally recommended. Although a charger without pulse function can charge a lithium battery in theory, it can still damage the lithium battery. Although the lithium battery has a protective plate, it can protect the battery from overcharge or overdischarge in theory. If overcharge protection voltage is triggered frequently during charging, then this is the case. The output voltage of a charger is not set correctly. After such a phenomenon, the backward battery will always lag behind. And protect panels as high as possible. Because the battery used in the battery box, usually can not see the consistency of the battery state, I do not know when, in case of its consistency problems, when the voltage is several V higher. The battery is going to be mildew. Please pay attention to it.
In fact, in order to overcome the large internal resistance of lead-acid battery charger in constant current charging, the charging voltage increased by about 5%, that is, you choose the same voltage charger to power lithium batteries, the voltage will be a little higher, because lead-acid internal resistance is large, constant current charging in order to achieve efficiency is in constant current When the voltage is raised, the lithium battery is very unfavorable.
The main reason is that there are two voltage points during the charging process of lead-acid batteries, the oxygen evolution voltage point is 13.8V, the hydrogen evolution voltage point is 14.7V, so the high constant voltage of lead-acid charger is set at 14.7V * block number; the low constant voltage (floating charge voltage) is set at 13.8V * block number.
If the protection voltage point of the lithium battery protector is 4.2V, then rest assured that you do not have to use a constant voltage and have charged, but the ordinary protector starting voltage of 4.25V, plus +/-0.035V error, is not very safe? 18650 may not be much, aluminum shell monomer difficult to say, many lithium batteries are using normal ordinary protector, protector plate Cut-off protection voltage 4.25V, so this protection may not work at a critical time.
Lithium-ion batteries have low internal resistance, such as 13 lithium-ion batteries, or 48 volts, with a cut-off voltage of 54.6 volts, whereas lead-acid batteries have a constant current cut-off voltage of 57.9 volts, several volts higher.
Of course, lead-acid batteries can be recharged from lithium batteries if improved, such as removing low-constant-voltage stage circuits and pulse circuits. If you look at the lithium charge curve, you can see that the constant current stage charged with about 96% of the total capacity; constant voltage and reduced current stage charged with only 4% of the capacity, if the light is turned off, then lithium has filled 99.5% of the capacity. Therefore, the lead-acid charger is charged with lithium, which means that the final balance and floating charge will be reduced by 0.5%. The low and constant voltage of lead can be charged to lithium battery, but it is just filled with dissatisfaction. However, lithium-ion power will not sulfide, fill it with dissatisfaction, and does not affect the use of life will be extended ah.
Another way is to open the enclosure, triode C series that resistance value increased 10 times, constant current only increased 0.5% voltage, and then adjust the constant voltage point, as far as possible to achieve a balanced battery voltage of 4.18V or so.