Using Smart V3 regulator with Li Batteries

[j1mthompson]

We are in the process of installing Li batteries (from Genasun) on a catamaran.
We currently have two ample V3 alternator regulators. One in each hull for each engine.
They are used with 75 amp alternators and were formerly charging AGM batteries.

The new Li batteries are best charged at 14.2 volts all the time. Bulk, Absorption, and float.
Most important is that we do not exceed 14.2 volts.
Do you have a table showing the Absorption and Float voltages for each of the 8 selectable battery types?
This would be most helpful.
On the ample web site:
It states that Ample Power Gel is 14.4 v absorption - that is too high for us.
It states that East Penn is 14.1 absorption - that is safe but a little low.
What battery type would you recommend for a 14.2 abortion and the highest float not to exceed 14.2?

[Coulomb]

You can lock the regulator in the ABS mode using Exide Gel setting on the dipswitch. Disconnect the temperature sensor wire and the voltage should be quite close to 14.2 Volts.

Don't take this as a recommendation because it isn't. All batteries require temperature compensation that is matched to their chemistry. And all batteries should be floated at a lower voltage than what it takes to fully charge them. Battery manufacturers are afraid to publish the real data because it might scare away potential users who don't have the proper charging equipment.

Without seeing the real charging requirements we can only guess that the temperature compensation profile in the SARV3 is not perfect for Li batteries.

The SARV3 is designed to charge lead-acid batteries, either liquid, gel, or agm units. Use it at your own risk on Li batteries.

[j1mthompson]

Thanks for info. We'll try the Exide Gel setting.
The Li Iron Phosphate batteries we are using have a recommeded charge voltage of 14.2 volts.
(This is 4 cells in series, each with 3.55 volts) With the Li chemistry there is no bulk, absorbtion or float voltage.
Just 14.2 all the time for charge. The current draw tapers off to 0 amps when they are fully charged.
There is temperature monitoring. It is not used for voltage regulation, just for protection. Over temperature will shut down
the charging circuit via a relay, it also shuts off the field current to the alternator via relay in the Li battery monitor/controller.
Thanks again.

[Coulomb]

Thanks for the info. Keep us posted on how it works for you.

Thanks.