Data Sheet

BMS10x0

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Counting is considered the dominant indicator. When at least one of the cells reaches

near the minimum or maximum cut off thresholds, where the voltage change is signiﬁcant

depending on the energy stored in the battery, this cell’s voltage becomes the dominant

indicator for the battery’s SoC. Observing the SoC allows the user to know when the

pack will be isolated from the load (0% SoC) and when it will be isolated from the charger

(100% SoC).

A time variable calculates in real time an estimation of battery’s depletion time in minutes

during discharging. During charging, the time variable provides the time in minutes that is

still needed for the battery to be fully charged.

In summary, the State of Charge is determined as a percentage of the current stored

energy versus the maximum battery capacity while operating in the nominal operating

area which is around 10% to 90% SoC, or based on the cell voltages when below 10% or

above 90%.

The State of Charge is readable via USB, CANbus, RS485, PWMOut and an optional

Bluetooth module.

Charging

The easiest and safest charging method for lithium cells is the so-called CC-CV, meaning

Constant Current – Constant Voltage.

Any conﬁgurable power supply may be used as a charger, as long as it can deliver

adequate current at the necessary voltage. For conﬁguring the charger’s voltage, please

refer to Cell Chemistry and Voltages section (Page 7, Table 3) and set the charger according

to the max voltage for the corresponding cell number and chemistry. The current should

be set lower or equal to the maximum current during charge speciﬁed by the cell

manufacturer. In case this value cannot be obtained, usually it is safe to consider the

maximum current during charge as the nominal cell capacity in Ah divided by 1 h. For

example, a 10 Ah battery would safely operate at up to 10 Ah/ 1 h = 10 A during charge.

Remember to conﬁgure your BMS system using the speciﬁed thresholds to ensure that

your battery operates in the safe operating area.

When the BMS system and the charger are properly conﬁgured, the charging process

will automatically begin after connecting the respective terminals. At the beginning, the

charger’s voltage will drop delivering 100% of the max charge current. While the pack is

being charged its voltage will at some point reach the nominal fully charged value and the

current will start to drop. The BMS system will continuously monitor and protect the pack

from any dangerous event.

If any of the cell voltages exceeds the maximum threshold or the pack is over heated,

the BMS system will pause the charging process allowing balancing to even out the

differences between the cells. When the system recognizes that the charging speed is

low, meaning slow voltage changes during charging, the BMS will activate the passive

balancing algorithm, extracting energy from the higher voltage cells so that the lower

voltage cells can catch up.

If for any reason the current exceeds the conﬁgured thresholds or in case a short circuit

event occurs, the BMS will automatically enable the circuit breaker to deactivate the

dangerous channel.

In a case where the charger parameters are not set with caution and the cells’ voltage

safe operating area is violated, the BMS will pause the process. Depending on the