16-cell BMS - Revision history

Johu: /* Communication */

2026-04-11T11:30:28Z

Communication

← Older revision		Revision as of 11:30, 11 April 2026
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	\|8		\|8
	\|tempmin		\|tempmin
	\|Minimum temp ~~+40~~ on module i		\|Minimum temp on module i - signed
	\|-		\|-
	\|56		\|56
	\|8		\|8
	\|tempmax		\|tempmax
	\|Maximum temp ~~+40~~ on module i		\|Maximum temp on module i - signed
	\|}		\|}
	The main module does not output its local accumulated values but accumulated values over all modules.		The main module does not output its local accumulated values but accumulated values over all modules.

Skr: added what happens if power is interrupted

2025-05-06T23:50:46Z

added what happens if power is interrupted

← Older revision		Revision as of 23:50, 6 May 2025
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	=== Power supply ===		=== Power supply ===
	The pins GND and 12V must be connected to a permanent 12V source in order to ensure correct operation. In other words, don't connect 12V for example to your cars ignition 12V that is interrupted whenever you stop the car.		The pins GND and 12V must be connected to a permanent 12V source in order to ensure correct operation. In other words, don't connect 12V for example to your cars ignition 12V that is interrupted whenever you stop the car. The BMS uses the STM32 NVRAM to store some long term process values, most importantly SoH. If you don't care about the latter you might as well interrupt the supply completely.

	The enable input of the first (main) module is connected to an interruptable 12V source. This input starts up the BMS. Enable can stay high but even a 1s pulse is enough to start the BMS, as it will then keep itself running as long as needed.		The enable input of the first (main) module is connected to an interruptable 12V source. This input starts up the BMS. Enable can stay high but even a 1s pulse is enough to start the BMS, as it will then keep itself running as long as needed.

Johu: Enable signal

2025-02-02T15:46:58Z

Enable signal

← Older revision		Revision as of 15:46, 2 February 2025
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	The pins GND and 12V must be connected to a permanent 12V source in order to ensure correct operation. In other words, don't connect 12V for example to your cars ignition 12V that is interrupted whenever you stop the car.		The pins GND and 12V must be connected to a permanent 12V source in order to ensure correct operation. In other words, don't connect 12V for example to your cars ignition 12V that is interrupted whenever you stop the car.

	The enable input of the first (main) module is connected to an interruptable 12V source. This input starts up the BMS.		The enable input of the first (main) module is connected to an interruptable 12V source. This input starts up the BMS. Enable can stay high but even a 1s pulse is enough to start the BMS, as it will then keep itself running as long as needed.

	The BMS will then keep running as long as current flows through the battery. 2 hours after it has measured the last current flow it will shut down. It will use these 2 hours to let the cells settle to their open circuit voltage and will do balancing and [[16-cell BMS#State of Health calculation\|SoH calculation]]. Afterwards it will shut itself down and consume only a few uA from your 12V source.		The BMS will then keep running as long as current flows through the battery. 2 hours after it has measured the last current flow it will shut down. It will use these 2 hours to let the cells settle to their open circuit voltage and will do balancing and [[16-cell BMS#State of Health calculation\|SoH calculation]]. Afterwards it will shut itself down and consume only a few uA from your 12V source.

Johu: Added SoH

2025-02-02T15:45:29Z

Added SoH

Show changes

Johu: Added spot values and SoC calculation

2025-02-02T15:22:20Z

Added spot values and SoC calculation

Show changes

Jacobsmess: /* Configuration Parameters */ added notes

2025-01-30T12:43:41Z

Configuration Parameters: added notes

← Older revision		Revision as of 12:43, 30 January 2025
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	\|16		\|16
	\|16		\|16
	\|Number of cells connected to the module		\|Number of cells connected to the module, power cycle required following saving parameters to update.
	\|-		\|-
	\|balmode		\|balmode
Line 198:		Line 198:
	2=Only dissipate high cells		2=Only dissipate high cells
	3=Do both		3=Do both

			By default balancing starts 60s after power up or in fact 60s after idcavg settled below 1A. You will see opmode changing to RunBalance
	\|-		\|-
	\|ubalance		\|ubalance
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	\|3		\|3
	\| 0		\| 0
	\|Temperature sensor 0=None, 1=Channel1, 2=Channel3, 3=Both		\|Temperature sensor 0=None, 1=Channel1, 2=Channel3, 3=Both (set tempsns 0 in dashboard if dropdown not availble and value set as -1)
	\|-		\|-
	\|tempres		\|tempres

Jacobsmess: /* Pinout */ correction of my correction

2025-01-29T13:02:21Z

Pinout: correction of my correction

← Older revision		Revision as of 13:02, 29 January 2025
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	On the top right is the vehicle interfacing or low voltage connector. From top to bottom it is low voltage GND, 12V, enable_in, enable_out, CANH, CANL. GND, 12V, CANH, CANL are connected to all modules in parallel whereas enable_out is chained to enable_in of the next module. The first enable_in must be connected to 12V whenever the BMS should become active, e.g. when charging or driving. The module with 12V on the enable_in auto-detects as "main" module, collects data from the subsequent modules and sends more high level CAN messages		On the top right is the vehicle interfacing or low voltage connector. From top to bottom it is low voltage GND, 12V, enable_in, enable_out, CANH, CANL. GND, 12V, CANH, CANL are connected to all modules in parallel whereas enable_out is chained to enable_in of the next module. The first enable_in must be connected to 12V whenever the BMS should become active, e.g. when charging or driving. The module with 12V on the enable_in auto-detects as "main" module, collects data from the subsequent modules and sends more high level CAN messages

	On the bottom right is the temperature sensor and current sensor input. Top to bottom it is tsensor1, tsensor1, 5V, CUR+, CUR-, GND. A single ended current sensor is just connected to CUR+.		On the bottom right is the temperature sensor and current sensor input. Top to bottom it is tsensor1+, tsensor1- (not silkscreened), tsensor2+ , tsensor2-(not silkscreened), 5V, CUR+, CUR-, GND. A single ended current sensor is just connected to CUR+.

	Right now the current sensor is only supported on the main module.		Right now the current sensor is only supported on the main module.

Jacobsmess: /* Pinout */ minor corrections

2025-01-29T12:39:29Z

Pinout: minor corrections

← Older revision		Revision as of 12:39, 29 January 2025
Line 21:		Line 21:
	On the top right is the vehicle interfacing or low voltage connector. From top to bottom it is low voltage GND, 12V, enable_in, enable_out, CANH, CANL. GND, 12V, CANH, CANL are connected to all modules in parallel whereas enable_out is chained to enable_in of the next module. The first enable_in must be connected to 12V whenever the BMS should become active, e.g. when charging or driving. The module with 12V on the enable_in auto-detects as "main" module, collects data from the subsequent modules and sends more high level CAN messages		On the top right is the vehicle interfacing or low voltage connector. From top to bottom it is low voltage GND, 12V, enable_in, enable_out, CANH, CANL. GND, 12V, CANH, CANL are connected to all modules in parallel whereas enable_out is chained to enable_in of the next module. The first enable_in must be connected to 12V whenever the BMS should become active, e.g. when charging or driving. The module with 12V on the enable_in auto-detects as "main" module, collects data from the subsequent modules and sends more high level CAN messages

	On the bottom right is the temperature sensor and current sensor input. Top to bottom it is tsensor1+, tsensor1~~-, tsensor2+, tsensor2-~~, 5V, CUR+, CUR-, GND. A single ended current sensor is just connected to CUR+.		On the bottom right is the temperature sensor and current sensor input. Top to bottom it is tsensor1, tsensor1, 5V, CUR+, CUR-, GND. A single ended current sensor is just connected to CUR+.

	Right now the current sensor is only supported on the main module.		Right now the current sensor is only supported on the main module.

Johu at 18:06, 26 January 2025

2025-01-26T18:06:58Z

← Older revision		Revision as of 18:06, 26 January 2025
Line 24:		Line 24:

	Right now the current sensor is only supported on the main module.		Right now the current sensor is only supported on the main module.

			=== Connector part numbers ===
			LV connector (supply, CAN, enable): header: Phoenix Contact 1803468 and 1803617 (screw terminal block)

			Temperature and current sensors: header: 640454-8, housing: 1375820-8, pins: 1445336-1

			cell taps: header: 1-640456-7, housing: 1-1375820-7, pins: 1445336-1

	== Communication ==		== Communication ==

Jacobsmess: /* Temperature limits */ spelling

2025-01-06T17:29:59Z

Temperature limits: spelling

← Older revision		Revision as of 17:29, 6 January 2025
Line 360:		Line 360:
	* Between '''43°C and 50°C''' charging with 100% to 0% of the charge curve is allowed, i.e. '''above 50°C''' charging is no longer allowed.		* Between '''43°C and 50°C''' charging with 100% to 0% of the charge curve is allowed, i.e. '''above 50°C''' charging is no longer allowed.

	Discharging is not limited at low temperatures ~~has~~ high discharge currents at low temperatures are not known to cause damage. As the battery heats up discharge current is limited, starting at '''46°C''' until discharging is no longer allowed when reaching '''53°C'''.		Discharging is not limited at low temperatures as high discharge currents at low temperatures are not known to cause damage. As the battery heats up discharge current is limited, starting at '''46°C''' until discharging is no longer allowed when reaching '''53°C'''.

	==== Energy limits ====		==== Energy limits ====