Integrating Victron Lithium batteries with VRLA

[Baronkrak]

5 x 100Ah 12V multi configuration VRLA.
2 x 90Ah 12.8V Victron Lithium in series.

The system wiring does not allow standard charging alternators to be overloaded by the Lithium batteries.

The system wiring does not require that inverters be connected to battery terminals.

https://www.cruisersforum.com/forums...me-248446.html

https://www.cruisersforum.com/forums...ml#post3424768

[Baronkrak]

To follow.

[Baronkrak]

Test 1 11/02/21

The test consisted in leaving the Phoenix inverter on (4A draw) until it disconnected on low voltage. (Factory set 18.6V). Surprise, surprise the inverter did not disconnect but the BMS and Battery Protect operated and protected the battery from cells under voltage. The inverter kept operating on the VLA battery until the voltage reached 18.6V then stopped. Alarm red green flashing.

Test 2
Recharging the Li battery from the 24V bus.
The current demand was similar to recharging a VLA of the same size:
30A for the first 20 minutes then 17A tapering down to 6A as the alternators (standard automotive) moved into float mode 27.6V. Raising the voltage by 0.6V increased the charging current from 6A to 17A.


…..…Voltmeter..IPad mini…Temp
5Y(24)…..12.2…….12.23….30…..3.08…..2.99….2.99…..3. 17…
..Alarm

SH(12)….12.7......12.64….30…..3.16....3.14…..3.15… ..3.19

[Baronkrak]

Originally Posted by alctel

So if I understand this thread correctly, a Victron Battery Protect device could be used as a standalone HVC contactor? (assuming you have a divided load bus and charge bus)...

The bus needs to be able to carry both load and charge current

Originally Posted by goboatingnow

Yes it can be so used but the over voltage is fixed at 16V and this is arguably too high for lithium HVC usage...

A charge Victron Battery Protect connected to a Victron Smart battery would be controlled by a Victron BMS and set to: C Li-ion mode.
The BMS monitor cells.
Over voltage is set at (cell voltage > 3.7V)

Originally Posted by alctel

…
actually adjustable - you just have to put the 'reconnect' voltage below the 'disconnect' voltage, which you set to 14.2 or whatever.
...

Dubious 14.2 does not exist.

[Baronkrak]

More information.

https://www.cruisersforum.com/forums...en-206424.html

[Baronkrak]

A warning from Century batteries.

*We do not recommend to float charge flooded Sealed Maintenance Free (calcium) batteries due to risk of drying out of the electrolyte.

https://www.centurybatteries.com.au/maintenance

For more precision.

Temperature(℃)
--0-----5-----10----15----20----25----30-----35----40
Float Voltage(Vpc)
2.36--2.35--2.33--2.32--2.30--2.28--2.27--2.25--2.24

For the one that cannot differentiate between Flat and Dead.

https://www.master-instruments.com.a...ual_ed2_1_.pdf