Settings

Control

Common settings

To change the common BMS settings, select the "Control → Common settings" section:

In this section:

• Cell capacity – nominal capacity of cells, Ah;
• Cell resistance – nominal (maximum) internal resistance of the cell, Ohm;
• Relax time (after charging) – a relaxation time after charging, second;
• Relax time (atfer discharging) – the relaxation time after discharging, second;
• Reset parameters– a command to reset cells state of charge, capacity, and resistance.

The values “Capacity” and “Resistance” are used to calculate the SOC of cells and the battery.

The values of “Relax time” are used to determine the state of the battery. If the battery is in a state of relaxation, the system recalculates the voltage on the cells to the state of charge of the battery.

The “Reset parameters” will reset:

• state of charge (new cell SOC values will be calculated based on cell voltage and “Uocv (open-circuit voltage) table”: in the “Control → SOC estimation” section);
• cell resistance to “Cell resistance” value;
• battery capacity to “Cell capacity” value.

The “Reset parameters” command is used for starting-up and adjustment of the battery.

SOC estimation

The BMS Mini device calculates the state of charge of the battery (SOC) using two algorithms:

• by open circuit voltage;
• by voltage and current.

It is recommended to use the algorithm of calculation of SOC by voltage and current.

To change the estimation algorithm for calculating the battery SOC, select the "Control → SOC estimation → Algorithm" section:

The following estimation algorithms supported:

• Voltage – by open circuit voltage;
• Current and voltage (simplified);
• Current and voltage (enhanced);

The “Voltage” SOC calculation algorithm calculates cells SOC based on the tabular dependence Uocv = Uocv(SOC, t °C).

The “Current and voltage (simplified)” SOC calculation algorithm works as follows:

• if I = 0, the battery is in a state of relaxation and the cell voltage Uocv is outside the [U_{ocv[point 1]}; U_{ocv[point 2]}], the SOC calculation based on the tabular dependence Uocv = Uocv(SOC, t °C);
• in any other cases, the SOC value is proportional to the charge (coulomb) passed through the battery (current time integral).

The “Current and voltage (enhanced)” SOC calculation algorithm differs from the simplified algorithm by online correction of effective capacitance. When using this algorithm, it is necessary to fine tune the tabular dependence Uocv = Uocv (SOC, t °C).

To change the algorithm for calculating the Final SOC, select the "Control → SOC estimation → Final SOC" section:

The following battery Final SOC calculation methods are supported:

• Minimal SOC – SOC of the modular battery is assumed to be the minimum SOC among the battery modules;
• Average SOC – SOC of the modular battery is taken equal to the arithmetic average of the SOC of the battery modules;
• Min-Max SOC – the battery SOC is calculated based on the minimum and maximum SOC of the cells. Final SOC will be a) 100% if any cell has 100% SOC, b) 0% if any cell has 0% SOC;
• Max-Min SOC – the battery SOC is calculated based on the minimum and maximum SOC of the cells. Final SOC will be a) 100% if all cells have 100% SOC, b) 0% if all cells have 0% SOC.

Other parameters:

• Scale the final SOC – a flag to scale the battery SOC by the following values;
• SOC corresponding to 0% – the battery SOC that sets to be 0%;
• SOC corresponding to 100% – the battery SOC that sets to be 100%.
• Uocv (open-circuit voltage) table – the dependence of the cell open circuit voltage Uocv on SOC and the cell temperature (selected for specific batteries);
• Linear zone - linear zone of the Uocv = Uocv(SOC, t°C) dependency, inside which the cell voltage changes insignificantly:
  • Linear zone: point 1 – starting point of the Uocv linear zone;
  • Linear zone: point 2 – ending point of the Uocv linear zone;
• Coulomb counting correction (temperature) – the dependence of battery capacity on temperature;
• Coulomb counting correction (cycles) – the dependence of battery capacity on the number of charge-discharge cycles.

SOC correction

The BMS Mini device can recalculate the battery SOC after long-term storage or after long-term working in the case when the battery was not charged fully or discharged totally. Recalculation is done based on the tabular dependency Uocv = Uocv (SOC, t) (see SOC estimation).

To configure parameters for periodically correcting the battery state of charge, select the "Control → SOC correction" section:

In this section:

• Enable – a flag to enable SOC correction;
• Shutdown period – a time the battery is off, day. If the BMS detects on its startup that it was off during the “Shutdown period” time, the BMS recalculates the battery state of charge based on the tabular dependency Uocv = Uocv (SOC, t);
• Correction period – a period of correcting the battery SOC, day. If the BMS detects that the last correction was more than the “Correction period” ago, the BMS recalculates the battery state of charge based on the tabular dependency Uocv = Uocv (SOC, t) and tunes it gradually during the “SOC change time”.
• SOC change time – a duration of the linear changing the battery SOC to the value calculated by the correction algorithm, minute;
• Ignore the linear zone – a flag to ignore linear SOC zone while correction;
• Last correction timestamp – time when last correction was made.

Resistance estimation

Calculation of the resistance of cells is carried out in two ways. The first method is used when the battery passes from a relaxation state to a charge or discharge state, wherein the cell resistance value

where U is the cell voltage measured in the charge or discharge state, V; U_ocv is the cell voltage measured in the state of relaxation (before switching to the state of charge or discharge); I_stable – stabilized current through the cell in the state of charge or discharge.

The second method is used for a stepwise change in the current through the cell, while the value of the cell resistance: 

provided that

where Q_max — the maximum cell capacity,U₂ — voltage on the cell at the moment when the stabilized current I_stable2 is flowing through it; U₁ — the voltage on the cell at the moment when the stabilized current I_stable1 flowing through it.

The stabilized current I_stable = I, if during the stabilization time the instantaneous current I is in the range from 0.95 × I to 1.05 × I.

To change parameters of the algorithm for calculating the cell resistance, select the "Control → Resistance estimation" section:

In this section:

• Current stabilization time, millisecond;
• Maximum calculation period – maximum time between resistance measurements. If more time has elapsed since the last determination of the stabilized current I_stable than is determined in this field, the resistance calculation is not performed, second;
• Maximum resistance factor – the coefficient of calculation of the maximum acceptable resistance of the cell;
• Minimum SOC – minimum cell SOC value for resistance calculation;
• Maximum SOC – maximum cell SOC value for resistance calculation.

The calculated resistance is accepted by the system as valid (and therefore updated) if its value is in the range from Resistance/2 to “Maximum resistance factor” × Resistance, where "Resistance" is the nominal resistance of the cell (see Common settings). If the calculated resistance value is greater than the value (Maximum resistance factor × Resistance), the updated resistance value will be equal to the value (Maximum resistance factor × Resistance).

Low SOC (signal)

To change the parameters of the generation a signal about low battery level, select the "Control → Low SOC (signal)" section:

In this section:

• Enable – a flag to enable signal generation;
• Minimum SOC, %;
• Tolerant SOC, %;
• Delay before setting the signal, second;
• Delay before clearing the signal, second;
• Lock – lock the signal until the device is reset.

Signal generation conditions:

• the battery SOC is less than the “Minimum SOC” value during the “Delay before setting the signal” time.

Conditions for clearing the signal:

• the battery SOC is greater than the “Tolerant SOC” during the “Delay before clearing the signal” time.

High charging current (signal)

To change the parameters of the generation high-current signal, select the "Control → High charging current (signal)" section:

In this section:

• Enable – a flag to enable signal generation;
• Maximum charging current, А;
• Tolerant charging current, А;
• Delay before setting the signal, second;
• Delay before clearing the signal, second;
• Lock – lock the signal until the device is reset.

Signal generation conditions:

• the measured current is greater than the “Maximum charging current” value during the “Delay before setting the signal” time.

Conditions for clearing the signal:

• the measured current is less than the “Tolerant charging current” value during the “Delay before clearing the signal” time.

Charge map

The BMS Mini device calculates maximum allowable charge current values in respect to SOC, battery temperature, contactor temperature and cell voltage.

Calculated current values are sending to a charger or an intellectual load over the CAN bus.

To configure parameters for determining the charge current limit, select the "Control → Charge map" section:

In this section:

• Enable – a flag to start calculation of the charge current limit;
• Maximum charge current – a maximum allowable value of the charge current (under normal conditions):
• Option 1: Limit charge current by the battery SOC and temperature – a flag to enable correction of maximum allowable charging current Kcs depending on SOC and battery temperature;
• Option 1: SOC x Temperature x Factor – the dependence of the correction factor on SOC and battery temperature;

• Option 2: Limit charge current by the contactor temperature – a flag to enable correction of maximum allowable charging current Kcc depending on contactor temperature;
• Option 2: Contactor temperature x Factor – the dependence of the correction factor on SOC and contactor temperature;

• Option 3: Limit charge current by the maximum cell voltage - a flag to enable correction of maximum allowable charging current Kcv depending on maximum cell voltage;
• Option 3: Cell voltage x Factor – the dependence of the correction factor on maximum cell voltage.

Value of the charge current limit at given SOC, temperature, contactors temperature and maximum cell voltage is calculated as follows:

Charging current limit = Maximum charging current × Kcs × Kcc × Kcv

Discharge map

The BMS Mini device calculates maximum allowable discharge current values in respect to SOC, battery temperature, contactor temperature and cell voltage.

Calculated current values are sending to a charger or an intellectual load over the CAN bus.

To configure parameters for determining the discharge current limit, select the "Control → Discharge map" section:

In this section:

• Enable – a flag to start calculation of the discharge current limit;
• Maximum discharge current – a maximum allowable value of the discharge current (under normal conditions):
• Option 1: Limit discharging current by the battery SOC and temperature – a flag to enable correction of maximum allowable discharging current Kds depending on SOC and temperature;
• Option 1: SOC x Temperature x Factor – the dependence of the correction factor on SOC and battery temperature;

• Option 2: Limit discharge current by the contactor temperature – a flag to enable correction of maximum allowable discharging current Kdc depending on contactor temperature;
• Option 2: Contactor temperature x Factor – the dependence of the correction factor on SOC and contactor temperature;

• Option 3: Limit discharge current by the cell voltage - a flag to enable correction of maximum allowable discharging current Kdv depending on minimum cell voltage;
• Option 3: Cell voltage x Factor – the dependence of the correction factor on minimum cell voltage.

Value of the discharge current limit at given SOC, temperature, contactors temperature and minimum cell voltage is calculated as follows:

Discharging current limit = Maximum discharging current × Kds × Kdc × Kdv

Charge

There are two contactors that serve charging the battery: a charging contactor and an allow charging contactor. With the help of the allow charging contactor, the BMS commands the charger to start or stop charging.

The device supports three charge control algorithms:

• charging is always allowed;
• charging is allowed when there is a signal “Charger connected”;
• charging is allowed when there is a signal “Charge request”.

If the "Always on" algorithm is selected, the charging contactor and the allow charging contactor are always closed. If at least one of the errors appears:

• Overvoltage;
• Overcurrent;
• High temperature (CH);
• Low temperature (CH);
• HYG offline (optional);
• Combilift offline (optional);
• Spirit offline (optional);
• Spirit charger error (optional);
• Short circuit (optional);
• High contactor temperature (optional);
• CH contactor cycles error;
• Critical error

both contactors are open (no current flows).

When the algorithm "On Charger connected" is selected, the control is performed as follows:

• If there is a signal “Charger connected” and there are no errors (see the list above), then through the delay time T_on the charging contactor and the allow charging contactor close;
• If the signal “Charger connected” disappears, the allow charging contactor opens and after the delay time T_off the charging contactor opens;
• If in the process of charging the voltage on the cell exceeds the “Ready to charge” level, the allow charging contactor opens (while the charging contactor remains closed);
• If errors in the list above occur the charging contactor and allow charging contactor open.

When the "On Charge request" algorithm selected, the control is performed as follows:

• If there is a signal “Charge request” and there are no errors (see the list above), then through the delay time T_on the charging contactor and the allow charging contactor close;
• If the signal “Charge request” disappears, the allow charging contactor opens and after the delay time T_off the charging contactor opens;
• If in the process of charging the voltage on the cell exceeds the “Ready to charge” level, the allow charging contactor opens (while the charging contactor remains closed);
• If errors in the list above occur the charging contactor and allow charging contactor open.

When the power down request occurs, the allow charging contactor opens immediately and the charging contactor opens after the delay T_off. Reclosing the charging contactor and allow charging contactor is performed if the power down request is removed.

To change the parameters of the battery charge control algorithm, select the "Control → Charge" section:

In this section:

• Enable – a flag to activate the charge control;
• Algorithm:
  • Always on – charging is always allowed;
  • On charger connected – charging is allowed when there is a signal “Charger connected”;
  • On charge request – charging is allowed when there is a signal “Charge request”;
• Current corresponding to charging – a current level to generate the "Charging current present" signal, A;
• Current corresponding to no charging – a current level to clear the "Charging current present" signal, A;
• Delay before starting charging – a time delay T_on before closing the charging contactor and the allow charging contactor, millisecond;
• Delay before stopping charging – a time delay T_off before opening the charging contactor, millisecond;
• Use custom delays before stopping charging (on errors) – a flag to enable manual settings of time delays T_off for specific errors;
• Custom delay: <error> – specific error delay, millisecond;
• Switch off the charging contactor on errors without delay – a flag to protectively open the charging contactor without a delay. In the opposite case, when an error is detected, the charging contactor opens always with the delay “Delay before stopping charging”;
• Control the precharging contactor – a flag that allows control of the precharging contactor;
• Voltage to clear the “Ready to charge” – a threshold voltage level on the cell, V; if the voltage of any cell is above this level, the “Ready to charge” (hence, the “Allow charging”) signal is cleared;
• Voltage to reset the “Ready to charge” – a tolerant voltage level on the cell, V; if all cell voltages are below the tolerant level, the “Ready to charge” (hence, the “Allow charging”) signal is set;
• Delay before recharging – a time after which the previously opened the allow charging contactor closes again, minute; to disable the operation by timeout set "Delay before recharging" to 0.

Discharge

The device controls the discharging contactor to connect battery to the load.

The device supports three algorithms to control battery discharging:

• load is always connected;
• load is connected when there is no signal “Charger connected”;
• load is connected when there is signal “Discharge request”.

When the algorithm "Always on" is selected, the discharging contactor is always closed. If at least one of the errors appears:

• Undervoltage;
• Overvoltage (optional);
• Overcurrent;
• High temperature (DCH);
• Low temperature (DCH) (optional);
• HYG offline (optional);
• Combilift offline (optional);
• Spirit offline (optional);
• Spirit charger error (optional);
• Short circuit (optional);
• High contactor temperature (optional);
• DCH contactor cycles error;
• Critical error

the discharging contactor opens.

If the algorithm "On Charger disconnected" is selected, the control is performed as follows:

• if there is no signal “Charger connected”, the charging contactor is opened and there are no errors (see the list above), then through the delay time T_on the discharging contactor closes;
• If the signal “Charger connected” appears or errors occur (see the list above), then after the delay time T_off the discharging contactor opens.

When the "On Discharge request" algorithm selected, the control is performed as follows:

• if there is signal “Discharge request”, the charging contactor is opened and there are no errors (see the list above), then through the delay time T_on the discharging contactor closes;
• If the signal “Discharge request” disappears or errors occur (see the list above), then after the delay time T_off the discharging contactor opens.

The device supports controlling the precharging contactor. The duration of switching on the precharging contactor before closing the discharging (load) contactor is adjusted.

When the power down request occurs, the discharging contactor opens after delay T_off. Reclosing the discharging contactor is performed if the power down request is removed.

To change the parameters of the battery discharge control algorithm, select the "Control → Discharge" section:

In this section:

• Enable – a flag to activate the discharge control;
• Algorithm:
  • Always on – load is always connected;
  • On charger disconnected – load is connected when there is no signal “Charger connected”;
  • On discharge request – load is connected when there is signal “Discharge request”;
• Current corresponding to discharging – a current level to generate the "Discharging current present" signal, А;
• Current indicating no discharging – a current level to clear the "Discharging current present" signal, А;
• Delay before starting discharging – a time delay T_on before closing the discharging contactor, millisecond;
• Delay before stopping discharging – a time delay T_off before opening the discharging contactor, millisecond;
• Use custom delays before stopping discharging (on errors) – a flag to enable manual settings of time delays T_off for specific errors;
• Custom delay: <error> – specific error delay, millisecond;
• Switch off the discharging contactor on errors without delay – a flag to protectively open the discharging contactor without a delay. In the opposite case, when an error is detected, the discharging contactor opens always with the delay “Delay before stopping discharging”.
• Precharge time – a duration of closing the precharge contactor before closing the discharging contactor, millisecond;
• Voltage to clear the “Ready to discharge” – a threshold voltage level on the cell, V; if the voltage of any cell is below this level, the “Ready to discharge” signal is cleared;
• Voltage to reset the “Ready to discharge” – a tolerant voltage level on the cell, V; if all cells voltages are above the tolerant level, the “Ready to discharge” signal is set;

Charge/Discharge

The BMS Mini device can control the charging/discharging contactor that is used to both charge and discharge the battery.

The charging/discharging contactor combines algorithms of charging and discharging contactor. It behaves as a charging contactor when «Charge request» or «Charger connected» are set, otherwise – as a discharging contactor.

The charging/discharging contactor control is configured in the “Control – Charge/Discharge” section:

In this section:

• Enable – a flag to enable the charge/discharge controller.

Discharge (AUX)

The BMS Mini device can control the power supply of external equipment using the auxiliary (AUX) discharging contactor. An example of external equipment can be an inverter that converts DC to AC to power a service laptop and other devices.

The power supply circuit of the external equipment using the auxiliary (AUX) discharging contactor is independent of the battery load circuit. The closing and opening of the auxiliary (AUX) discharging contactor is performed according to its program.

If the power supply function of the external equipment is enabled, the auxiliary (AUX) discharging contactor closes. The opening of this contactor occurs on three independent conditions:

• the battery has low SOC;
• the battery voltage is out of range;
• the battery system errors are detected.

To change the parameters of the powering of external equipment, select the "Control → Discharge (AUX)" section:

In this section:

• Enable – a flag to activate the auxiliary discharge control;
• Switch off the discharging (AUX) contactor if the SOC is too low;
• Minimum SOC – a minimum SOC value, when reached, the auxiliary (AUX) discharging contactor opens, %;
• Tolerant SOC – a permissive SOC value, upon reaching which the auxiliary (AUX) discharging contactor re-closes, %;
• Switch off the discharging (AUX) contactor if the battery voltage is out of the range;
• Minimum voltage – minimum battery voltage, V;
• Maximum voltage – maximum battery voltage, V;
• Switch off the discharging (AUX) contactor on errors – the auxiliary (AUX) discharging contactor opens if the following errors occur: Undervoltage, Overcurrent, High temperature (DCH), Short circuit, Critical error.

Main contactor

The BMS Mini device controls the main contactor. The main contactor is usually placed in the common (minus) battery line for opening the charge and discharge circuits in a case of sealing of the charging or discharging contactors.

The main contactor closes if there are no errors from the list below:

• Overcurrent;
• Undervoltage;
• Overvoltage;
• High temperature (CH);
• High temperature (DCH);
• Unallowable charging;
• Critical error.

The main contactor opens if the charging and discharging contactors are opened and any of the following conditions is met:

• charging or discharging current is detected during a set time;
• voltage of any cell is lower than the minimum cell voltage configured in the section "Protections → Undervoltage" during a set time;
• voltage of any cell is greater than the maximum cell voltage configured in the section "Protections → Overvoltage" during a set time;
• temperature of any cell is greater than the maximum cell temperature configured in the section "Protections → High temperature" during a set time;
• Critical error stays on during a set time.

To change the parameters of the main contactor, select the "Control → Main contactor" section:

In this section:

• Enable – a flag to enable the main contactor control;
• Delay before opening the contactor – a time which is used to detect conditions for opening the contactor, second;
• Keep the contactor open until the device is restarted – a flag for keeping the main contactor opened until the system be reset.

Cell balancing

Balancing makes the voltage of all cells be equal to the minimum cell voltage.

The following balancing rules are supported:

• only when the battery is charging (current I > 0) and some time until the battery is relaxed;
• when the battery is charging (current I > 0) or when the battery is in a state of relaxation;
• always (regardless of battery state).

A balancing resistor is connected to the cell if:

• the voltage on the cell is higher than the starting voltage of the balancing;
• the difference between the cell voltage and the minimum voltage among the cells of the battery is greater than the balancing deviation.

To change the cell balancing parameters, select the "Control → Cell balancing" section:

In this section:

• Enable – a flag to enable cell balancing;
• Balancing rule:
  • Balance on charge;
  • Balance on charge or relaxed;
  • Balance always;

• Minimum cell voltage to start balancing, V;
• Balancing deviation, V.

Power down

The BMS Mini device can shut down itself if the battery voltage is low or the battery is idle for a long time.

Shutting down the battery system is performed according to the following conditions:

• the battery voltage is below the minimum level;
• the “Charger connected” signal is cleared for 60 seconds.

The BMS Mini device also shuts down the battery if it stays in the “Charging OFF”, “Discharging OFF”, “Relaxed (after charging)” or “Relaxed (after discharging)” for the set time.

To change the parameters of the power down control, select the "Control → Power down" section:

In this section:

• Minimum voltage to power down – a minimum voltage level of the battery below which the BMS commands to shut down the battery, V;
• Idle time to power down – a time of battery inactivity after which the battery is shut down, minute;
• Wait the "Power up/down request" is cleared (on startup) – a flag to enable delay for clearing the “Power up/down request” signal while starting the BMS.

Heater

To change the parameters of the heater control algorithm, select the "Control → Heater" section:

In this section:

• Enable – a flag to enable heater control;
• Minimum cell temperature, °C;
• Tolerant cell temperature, °C;
• Delay before starting the heater, millisecond;
• Delay before stopping the heater, millisecond;
• Switch off the heater on errors (Undervoltage, Overcurrent, High temperature, Short circuit or Critical error).

As a result of operating the heating algorithm, the “Heater” signal is generated.

Conditions for signal generation:

• The minimum temperature among all cells of the battery is less than the “Minimum cell temperature” value during the “Delay before starting the heater” time.

Conditions for clearing the signal:

• the minimum temperature among all cells of the battery is greater than the “Tolerant cell temperature” value during the “Delay before stopping the heater” time.

Cooler

To change the parameters of the cooler control algorithm, select the "Control → Cooler" section:

In this section:

• Enable – a flag to enable cooler control;
• Maximum cell temperature, °C;
• Tolerant cell temperature, °C;
• Delay before starting the cooler, millisecond;
• Delay before stopping the cooler, millisecond;
• Switch off the cooler contactor on errors (Undervoltage, Overcurrent, Low temperature, Short circuit or Critical error).

As a result of operating the cooling algorithm, the "Cooler" signal is generated.

Conditions for signal generation:

• the maximum temperature among all cells of the battery is greater than the “Maximum cell temperature” value during the “Delay before starting the cooler” time.

Conditions for clearing the signal:

• the maximum temperature among all cells of the battery is less than the “Tolerant cell temperature” value during the “Delay before stopping the cooler” time.

Cell analysis

Discharge characteristics of the battery – the dependence Uocv = Uocv (DOD) – is used to determine the tabular dependence Uocv = Uocv (SOC, t °C), which is necessary for calculating the state of charge of the battery.

The BMS Mini device can automatically determine the battery discharge characteristic.

Before starting the process of determining the discharge characteristic, it is necessary to prepare a BMS:

1. Charge the battery.
2. Connect a resistive load to the discharging contactor, which will provide a discharge current of 0.5C (where C is the cell capacitance).

To configure parameters for determining the discharge characteristic of the battery, select the "Control → Cell analysis" section:

In this section:

• Enable – a flag to enable cell analysis;
• Discharge step, Ah;
• Delta voltage – a maximum allowable voltage drop for the cell, V;
• Cell index – a position of the analyzed cell;
• Analyse the most discharged cell – a flag to analyse of the least charged cell (in this case, the value “Cell index” is ignored).

Discharge step should be set equal to

Discharge step= С/21,

where C is the cell capacity.

The discharge characteristic will be constructed for the given cell (its position is determined by the field “Cell index”).

The algorithm for determining the discharge characteristic of the battery will be started if the “Enable” flag is set. From this moment, the control of the discharge contactor is performed by this algorithm.

Algorithm steps:

1. DOD = 0.
2. Opening the discharging contactor.
3. Waiting for the relaxation of the battery.
4. Measuring Uocv = U.
5. Saving the point of the discharge characteristic (Q, U_OCV).
6. Closing of the discharging contactor. DOD₁ = DOD + Discharge step, U₁ = U
7. If DOD = DOD₁ or U < (U₁ – Delta voltage), then go to step 2.
8. If the "Undervoltage" error is detected, then the end of the algorithm.

During the operation of the algorithm, a file with the name "CELLANALYSIS.TXT" in the CSV format will be created on the SD card.

File structure:

Parameter names:

• Time – date and time;
• DOD – depth of discharge, Ah;
• Cell – position of the analyzed cell for which OCV and Resistance values are provided;
• OCV – cell voltage Uocv, V;
• Resistance – cell resistance, Ohm.