Riden RD60 Series, Manual, Page: 72 / 77

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Every type of battery has its own recommendations on how to set the charge current with this
method, but in general, charging an empty battery at 0.1C up to 100% of the rated capacity can
be relatively safe. Like with the time limit, the capacity limit you set must be adapted to the
initial charge state of the battery, as the charger cannot know the pre-existing charge.
The RD60xx allows you to set a maximum charge limit, via ‘ CutOff cap. ’
21.4.3. Current limit
Another simple method is the current limit. When the charge current drops below a specific limit,
the charge is interrupted. This is a very basic method and can be relatively safe. It is however
not recommended for NiMH or NiCd batteries, where dv/dt is better suited. Apart from that, it
may fail easily if the charge voltage is set too high. But even when the charge voltage is set
correctly, it may fail, especially in worn batteries, due to leakage in the battery. Overall it may be
wise to limit this method with other limit methods.
The RD60xx allows you to set a charge current limit, via CutOff current .
Be aware that this limit is a lower limit, not an upper limit.
21.4.4. Temperature limit
High temperatures can shorten the life of almost all battery types. Also, some battery types, like
Lithium-ion and NiMH, show a rather sharp increase in temperature once they reach a full
charge.
Therefore, it can be very interesting to use the external temperature sensor of the RD60xx for
the charging process, be it for detection of end of charge, or just as an additional safety
measure. This is not fool-proof however:
● High charge currents can cause heating by itself, and cut the charging short too soon.
● Detecting a temperature rise in large batteries can be hard due the thermal mass, and/or
convection, potentially causing the charge to continue too long.
● In a pack of batteries, some cells will heat up before others. You may be measuring at
the wrong location.
The RD60xx allows you to set a maximum temperature, via Cutoff temp . Be aware that this kind
of doubles up with OTP (EXT) , but the latter is more to be used as a final safety measure, not
specifically for battery charging.
Both of these settings are absolute upper temperature limits, you will NOT be able to:
● Specify temperature slopes (increase or temperature in a specific time), which would be
useful for Lithium-ion for example.
● Adapt the charge current to the temperature, as can be interesting for Lead Acid float
charging.