Milk crate build without solar

[mikebow16]

So I saw the milk crate build on YouTube and thought this would work as a backup for an aquarium pump I’m running. I’m treating this like a ups and super simple battery, charger and inverter. Chins 50ah 12v battery, 600w inverter, CV power supply. I’ve been searching online and really can’t find any definitive information can I leave the power supply on 24/7 while the inverter is running a 50w load then when the power goes out the battery would take over until the power comes back on? Will this shorten the life of the battery or cause an unsafe condition? Do I need to cycle the battery daily 16 hours charging 6 hours discharging? Or do I need a different charger?

Thanks

 

[timselectric]

So I saw the milk crate build on YouTube and thought this would work as a backup for an aquarium pump I’m running. I’m treating this like a ups and super simple battery, charger and inverter. Chins 50ah 12v battery, 600w inverter, CV power supply. I’ve been searching online and really can’t find any definitive information can I leave the power supply on 24/7 while the inverter is running a 50w load then when the power goes out the battery would take over until the power comes back on? Will this shorten the life of the battery or cause an unsafe condition? Do I need to cycle the battery daily 16 hours charging 6 hours discharging? Or do I need a different charger?

Thanks

LFP batteries are fine to keep connected. But, I wouldn't keep them at 100%. Set the charging voltage to about 90% and the battery won't be stressed at all. 13.8v would be my recommendation.

 

[mikebow16]

LFP batteries are fine to keep connected. But, I wouldn't keep them at 100%. Set the charging voltage to about 90% and the battery won't be stressed at all. 13.8v would be my recommendation.

So charge at 14.4 then reduce it or charge at 13.8? I thought that the battery won’t charge at that voltage

 

[timselectric]

So charge at 14.4 then reduce it or charge at 13.8? I thought that the battery won’t charge at that voltage

Either is fine.
14.4 will get you to full, faster. Just don't keep it there.

 

[chrisski]

So I saw the milk crate build on YouTube and thought this would work as a backup for an aquarium pump I’m running. I’m treating this like a ups and super simple battery, charger and inverter. Chins 50ah 12v battery, 600w inverter, CV power supply. I’ve been searching online and really can’t find any definitive information can I leave the power supply on 24/7 while the inverter is running a 50w load then when the power goes out the battery would take over until the power comes back on? Will this shorten the life of the battery or cause an unsafe condition? Do I need to cycle the battery daily 16 hours charging 6 hours discharging? Or do I need a different charger?

This will run an aquarium pump at least 8 hours straight.

Are you against using lead acid batteries? The UPS battery I just replaced was a sealed lead acid battery. If temp matters both hot and cold, then lead acid could be better. 50 watts is not a lot of power, perhaps 6 amps at 12 volts. An 80 ah to 100 ah lead acid battery would get you as much power as a 50 ah lithium battery.

I always thought lithium batteries were not the choice for long standby operations. Most of the threads go like this:

https://diysolarforum.com/threads/lithium-for-ups.24920/

 

[timselectric]

This will run an aquarium pump at least 8 hours straight.

Are you against using lead acid batteries? The UPS battery I just replaced was a sealed lead acid battery. If temp matters both hot and cold, then lead acid could be better. 50 watts is not a lot of power, perhaps 6 amps at 12 volts. An 80 ah to 100 ah lead acid battery would get you as much power as a 50 ah lithium battery.

I always thought lithium batteries were not the choice for long standby operations. Most of the threads go like this:

https://diysolarforum.com/threads/lithium-for-ups.24920/

I'm actually replacing my UPS batteries with LFP, as they reach their end. As long as you don't keep them at the top or bottom of the curve, I don't see any reason not to.

 

[mikebow16]

This will run an aquarium pump at least 8 hours straight.

Are you against using lead acid batteries? The UPS battery I just replaced was a sealed lead acid battery. If temp matters both hot and cold, then lead acid could be better. 50 watts is not a lot of power, perhaps 6 amps at 12 volts. An 80 ah to 100 ah lead acid battery would get you as much power as a 50 ah lithium battery.

I always thought lithium batteries were not the choice for long standby operations. Most of the threads go like this:

https://diysolarforum.com/threads/lithium-for-ups.24920/

My main pump is backed up with a lead acid battery for this pump I wanted to try lifepo4 battery due to the size and weight also since this pump cannot accept 12v directly I have to run an inverter. I looked at a traditional ups but even the large ones would only last about two hours. I wanted something that would give me time to get home from work and start up the generator. If this setup works out when my lead acid battery stops working I’ll switch over to a lifepo4 battery.

 

[mikebow16]

Here is an in work pic of the setup so far