How to supply limited power to a hungry BMS for li-ion charging
You'd need to post a datasheet for the DC power supply. The DC power supply, like you said, can only put out 2A. The 8A on the BMS is just a limit, it'll take 2A just fine. The balancing usually comes in the form of a switched resistor. Active balancing is quite expensive and bulky. The most likely scenario is that the BMS is just passing through your input to charge and taking care of the balancing/cut-offs.
When a DC power supply says &quot;Over Current Protection&quot; that is usually in the form of a hiccup-mode where the converter will turn on at full power, realize it is still overloaded, and then shut back down. Sometimes this happens indefinitely, sometimes only a few hiccups before latching off.
CC is an additional circuit so not all power supplies will have one, and if they do, they usually specify it. Without a datasheet/more info for every part involved there is no &quot;right&quot; answer.
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