When charging a battery, the charging current must be controlled in constant‑current (CC) mode, so it is important to select a power supply that supports constant‑current operation.

If a general-purpose power supply without a constant‑current function is used for battery charging, the unit will enter an over‑current protection (OCP) state. There are several types of OCP characteristics, and some models can be modified through minor design changes to enable constant‑current operation.
Below are the typical types of over‑current protection (load characteristics).

Among the three protection methods described above, selecting a model with a “reverse‑L fold‑back characteristic” allows the battery to be charged at a constant current by utilizing the constant‑current region (i2).
However, in many general‑purpose power supplies, the relationship is typically “rated current i1 < over‑current protection setting i2”.
If used as‑is, the power supply would operate outside its rated range, which may place excessive stress on the unit.
Therefore, a minor design modification is required so that “over‑current protection setting i2 < rated current i1”.
For details on whether this modification can be supported for a specific model, please contact us separately.