Switch to lithium battery

[Richardmatheson]

I have a rookie question about switching to lithium batteries.
I had to replace my 2 6V lead acid batteries and decided to go to the lithium phosphate battery. I read what I could and changed the converter/ charger and bought the VictronConnect 712 monitor. I just finished all the installation and hooked up my 3200 watt generator to fully charge the 120ah battery and check that everything was working. (303 is in a storage yard) everything worked great I think, except once the new battery hit 13.7 volts, it didn’t seem to want to go any higher. Shouldn’t have gone to 14.6 volts? Am I missing something? Thanks.

[MoonShadow_1911]

I have a rookie question about switching to lithium batteries.
I had to replace my 2 6V lead acid batteries and decided to go to the lithium phosphate battery. I read what I could and changed the converter/ charger and bought the VictronConnect 712 monitor. I just finished all the installation and hooked up my 3200 watt generator to fully charge the 120ah battery and check that everything was working. (303 is in a storage yard) everything worked great I think, except once the new battery hit 13.7 volts, it didn’t seem to want to go any higher. Shouldn’t have gone to 14.6 volts? Am I missing something? Thanks.

Did you buy a converter that is for LiFePO batteries?

Did you configure the converter (if needed) for LiFePO batteries?

Sent from my SM-N986U using Tapatalk

[xrated]

I have a rookie question about switching to lithium batteries.
I had to replace my 2 6V lead acid batteries and decided to go to the lithium phosphate battery. I read what I could and changed the converter/ charger and bought the VictronConnect 712 monitor. I just finished all the installation and hooked up my 3200 watt generator to fully charge the 120ah battery and check that everything was working. (303 is in a storage yard) everything worked great I think, except once the new battery hit 13.7 volts, it didn’t seem to want to go any higher. Shouldn’t have gone to 14.6 volts? Am I missing something? Thanks.

First question is which converter/charger......brand and model? Secondly, the battery may have been charged enough when you got it that when the charger was hooked up, it sensed the battery voltage and went to float mode.

[Richardmatheson]

Thanks for the replies. Yes the converter is specific for lifepo4 batteries. It’s a progressive dynamics PD9160alv. They recommended it to replace the stock converter that came originally with my 303. The float mode suggestion seems probable, as the battery did arrive with about a 12.8 volt charge. I just assumed the new converter would automatically top it up to 14.6 volts and then shut down.

[huntindog]

It sounds like you may be having wiring voltage drop issues. Check the voltage at the convertor, and at the batteries.

[xrated]

Thanks for the replies. Yes the converter is specific for lifepo4 batteries. It’s a progressive dynamics PD9160alv. They recommended it to replace the stock converter that came originally with my 303. The float mode suggestion seems probable, as the battery did arrive with about a 12.8 volt charge. I just assumed the new converter would automatically top it up to 14.6 volts and then shut down.

12.8V on a LFP battery is a pretty low state of charge.....probably down around 20%. My next question would be, what are you using to verify the actual battery voltage....the monitor on the trailer or a Digital Volt Meter? If it truly was 12.8V as measured by an accurate meter, the new charger definitely should have started out charging at it's Bulk/Boost charge voltage of 14.6V. Once the charger senses that the battery is almost fully charged, based on the drop of current going to the battery (tail current), it then reverts to idle, or as some call it float voltage....13.6V. Your charger is strictly a two stage charger, so you should be seeing either 14.6 volts out of it, or 13.6 volts out of it. The charger does not shut down once the battery is charged, as it also is able to provide voltage for the trailer 12V system....and that is the 13.6V that you would see once the battery is fully charged.

Another point of info....once the battery is fully charged...AND has been at rest for a few hours or so, the battery will likely settle down to about 13.8 volts. This voltage would be it's "resting" voltage and you could read that voltage with a Digital Multi Meter (DMM). That resting voltage is a few tenths higher than the Idle or float voltage of the charger, but the bottom line is that the charger does go into bulk/boost mode when it needs to.....and if the battery truly was only 12.8 volts when you got it, the charger should have gone to the bulk/boost mode (14.6V).....for some period of time, until the amount of tail current tells it to switch to idle or float voltage (13.6)

[Richardmatheson]

Thank you for the information. It makes sense to me now and everything seems to be working as it should.

[Always Learning]

the new charger definitely should have started out charging at it's Bulk/Boost charge voltage of 14.6V. Once the charger senses that the battery is almost fully charged, based on the drop of current going to the battery (tail current), it then reverts to idle, or as some call it float voltage....13.6V.

xrted, are you sure about the 14.6 dropping to 13.6? What you describe is how my Victron solar controller works but not how my progressive dynamics PD9160alv converter works. My progressive dynamics PD9160alv converter goes to 14.6 and stays there but reduces the amps as the batteries get charged. I have two 100ah Battle Born batteries. I did talk to Battle Born about this one time and they said that my converter was working correctly. Since I only use my solar and not the PD9160alv unless I have cloudy day I did not check into it more.

[xrated]

xrted, are you sure about the 14.6 dropping to 13.6? What you describe is how my Victron solar controller works but not how my progressive dynamics PD9160alv converter works. My progressive dynamics PD9160alv converter goes to 14.6 and stays there but reduces the amps as the batteries get charged. I have two 100ah Battle Born batteries. I did talk to Battle Born about this one time and they said that my converter was working correctly. Since I only use my solar and not the PD9160alv unless I have cloudy day I did not check into it more.

https://www.progressivedyn.com/pd9100l/

You may have an older model of this. Prior to August 2020, if I'm not mistaken they were single stage

[Always Learning]

https://www.progressivedyn.com/pd9100l/

You may have an older model of this. Prior to August 2020, if I'm not mistaken they were single stage

Thanks for the info.