POWER:BAT: clarified the sign for the current fields

ardupilot/equipment/power/20004.BatteryInfoAux.uavcan

@@ -24,7 +24,7 @@ uint16 cycle_count
 uint16 over_discharge_count
 
 # Max instantaneous current draw since last message
-float16 max_current                 # [Ampere]
+float16 max_current                 # [Ampere] Positive: defined as a discharge current. Negative: defined as a charging current
 
 # Nominal voltage of the battery pack
 # the nominal Voltage can be used for conversion between Wh and Ah

cuav/equipment/power/20300.CBAT.uavcan

@@ -2,30 +2,30 @@
 # support for CUAV Smart Battery on UAVCAN
 #
 
-float32 temperature                 # The surface temperature of the battery
-float32 voltage                     # The total voltage of the battery
-float32[<=15] voltage_cell          # Battery individual cell voltages
-uint8 cell_count                    # Number of cells
-float32 current                     # The current flowing through the sense resistor
-float32 average_current             # The average current flowing through the sense resistor
-float32 average_power               # The average power of the current discharge
-float32 available_energy            # The predicted charge or energy remaining in the battery
-float32 remaining_capacity          # The compensated battery capacity remaining
-float32 full_charge_capacity        # The compensated capacity of the battery when fully charged
-float32 design_capacity             # The design capacity of the battery
-uint16 average_time_to_empty        # The predicted remaining battery life at the present rate of discharge, in minutes
-uint16 average_time_to_full         # The predicted remaining time until the battery reaches full charge, in minutes
-uint7 state_of_health               # Health of the battery
-uint7 state_of_charge               # Percent of the full charge [0, 100]
-uint7 max_error                     # max error, expected margin of error in % in the state-of-charge calculation with a range of 1 to 100%
-uint16 serial_number                # serial number of the battery pack
-uint16 manufacture_date             # manufacture date, part of serial number of the battery pack
-uint16 cycle_count                  # number of discharge cycles the battery has experienced
-uint16 over_discharge_count         # Number of battery overdischarge
-float32 passed_charge               # The amount of charge passing through the sense resistor
-float32 nominal_voltage             # Nominal voltage of the battery pack
-bool is_powering_off                # Power off event imminent indication, false if unknown
-uint16 interface_error              # interface error counter
+float32 temperature                 # [Kelvin]      Surface temperature of the battery
+float32 voltage                     # [Volt]        Total voltage of the battery
+float32[<=15] voltage_cell          # [Volt]        Individual cell voltages
+uint8 cell_count                    # [-]           Number of cells
+float32 current                     # [Ampere]      Positive: defined as a discharge current. Negative: defined as a charging current
+float32 average_current             # [Ampere]      Average current. Positive: defined as a discharge current. Negative: defined as a charging current
+float32 average_power               # [Watt]        Average power consumption over the last 10 seconds
+float32 available_energy            # [Joule]       Predicted charge or energy remaining in the battery
+float32 remaining_capacity          # [mAh] Compensated battery remaining capacity
+float32 full_charge_capacity        # [mAh] Compensated capacity of the battery when fully charged
+float32 design_capacity             # [mAh] Design capacity of the battery
+uint16 average_time_to_empty        # [minute]      Predicted remaining battery life at the present rate of discharge
+uint16 average_time_to_full         # [minute]      Predicted remaining time until the battery reaches full charge
+uint7 state_of_health               # [Percent]     Health of the battery
+uint7 state_of_charge               # [Percent]     Percent of the full charge [0, 100]
+uint7 max_error                     # [Percent]     Expected margin of error in the state-of-charge calculation [1, 100]
+uint16 serial_number                # [-]           Serial number of the battery pack
+uint16 manufacture_date             # [-]           Manufacture date, part of serial number of the battery pack
+uint16 cycle_count                  # [-]           Number of discharge cycles the battery has experienced
+uint16 over_discharge_count         # [-]           Number of battery overdischarge events
+float32 passed_charge               # [Coulomb]     Amount of charge that has passed through the sense resistor
+float32 nominal_voltage             # [Volt]        Nominal voltage of the battery pack
+bool is_powering_off                # [-]           Power off event imminent indication, false if unknown
+uint16 interface_error              # [-]           Interface error counter
 
 uint11 STATUS_FLAG_IN_USE       = 1     # The battery is currently used as a power supply
 uint11 STATUS_FLAG_CHARGING     = 2     # Charger is active

uavcan/equipment/power/1092.BatteryInfo.uavcan

@@ -14,7 +14,7 @@
 #
 float16 temperature             # [Kelvin]
 float16 voltage                 # [Volt]
-float16 current                 # [Ampere]
+float16 current                 # [Ampere]      Positive: defined as a discharge current. Negative: defined as a charging current
 float16 average_power_10sec     # [Watt]        Average power consumption over the last 10 seconds
 float16 remaining_capacity_wh   # [Watt hours]  Will be increasing during charging
 float16 full_charge_capacity_wh # [Watt hours]  Predicted battery capacity when it is fully charged. Falls with aging