Discharging NOT Charging a 12v LiFePo4 with Old Mod. Sine Wave Inverter Ok?

[sun_of_a...]

I have an old Everstart 400w modified sine wave car (cigerette lighter) inverter. I have new 12v LiFePo4 batteries.

Does it damage them at all to discharge them individually with this inverter? Not charge, just discharge?

Would the same go for an old 12v pure sine wave inverter designed for the lead acid battery days?

It is my understanding that CHARGING 12v LiFePo4 with a modified or pure sine wave 12v inverter ac 110v charger to charge 12v auto batteries is not good for LiFePo4s. Same for discharging?

The batteries are new and came fully charged. I will discharge them all to 50% for storage until I put my 12v system together. BUT I may use them a bit... but I plan to keep the usage and state of charge the same among batteries for the eventual battery bank.

Thank you!

EDITED

 

[sunshine_eggo]

Inverters don't charge. MSW inverter/chargers put out DC when charging, not AC, so there's not a MSW in that regard, so no concern there either.

I wouldn't hesitate to put a MSW inverter on a LFP battery. I actually did that here when I did a discharge test:

Pseudo self-discharge exercise

Battery: 4S 25Ah Topband Navitas 3C cells. 120A JBD BMS UART to USB adapter from Overkillsolar Bluetooth module uses the BMS UART connector, so it was not installed. VRM: Raspberry Pi 3 B+ 1GB (RPi) 256G MicroSD Venus OS 3.11 start, 3.12 end @Louisvdw serial battery driver There were NO LOADS...

diysolarforum.com

 

[sun_of_a...]

Inverters don't charge. MSW inverter/chargers put out DC when charging, not AC, so there's not a MSW in that regard, so no concern there either.

I wouldn't hesitate to put a MSW inverter on a LFP battery. I actually did that here when I did a discharge test:

Pseudo self-discharge exercise

Battery: 4S 25Ah Topband Navitas 3C cells. 120A JBD BMS UART to USB adapter from Overkillsolar Bluetooth module uses the BMS UART connector, so it was not installed. VRM: Raspberry Pi 3 B+ 1GB (RPi) 256G MicroSD Venus OS 3.11 start, 3.12 end @Louisvdw serial battery driver There were NO LOADS...

diysolarforum.com

I sure appreciate the response sunshine, I mispoke. I meant that my understanding is not to use old 110v ac chargers made fto charge 12v auto batteries to charge LiFePo4s. Is that true?

And you say I can safely discharge/ use/load my LiFePo4s using this old 12v 400w cigerette lighter inverter? Safe for batteries?

 

[sunshine_eggo]

I sure appreciate the response sunshine, I mispoke. I meant that my understanding is not to use old 110v ac chargers made fto charge 12v auto batteries to charge LiFePo4s. Is that true?

It can be true, but not in most cases. The charger voltages are what matter.

And you say I can safely discharge/ use/load my LiFePo4s using this old 12v 400w cigerette lighter inverter? Safe for batteries?

I would assume it's no better/worse than the 750W MSW Amazon special I used in that battery test.

The straight line of constant slope indicates the draw from the battery was a relatively constant amperage:

 

[sun_of_a...]

It can be true, but not in most cases. The charger voltages are what matter.



I would assume it's no better/worse than the 750W MSW Amazon special I used in that battery test.

The straight line of constant slope indicates the draw from the battery was a relatively constant amperage:

View attachment 187883

Thank you sunshine. Really appreciate the help!