LifePo4 battery for Sump Pump Backup

[gattaca]

@bedpan Thanks for your posting and updates.

Would you take a look at my posting here and let me know what you think? -> https://diysolarforum.com/threads/b...back-up-battery-replacement.65138/post-816535

I'm in similar situation where I'm about to drop $170 each on 4 x lead-acid batteries to keep my existing setup functional. I wanted to consider removing the existing _backup_ setup and just doing a simple 12V SUMP, 100-200A LiFePO4 with Victron charger and pump controller.

What's not clear to me is if I can :

1. Simply connect the Victron Battery Charger to the LiFePO4 battery then from the 12V terminals that 12V backup SUMP controller and let the Victron keep the battery good-to-go. Of course I'd use Blue Sea terminal fuses and on/off switch disconnect. Can it be really this simple?
2. I'm unclear if I really need anything else from Victron to make this for for a high quality LiFeP04 setup. Do I need any sort of other BMS or control setups?

Thanks!

 

[bedpan]

@bedpan Thanks for your posting and updates.

Would you take a look at my posting here and let me know what you think? -> https://diysolarforum.com/threads/b...back-up-battery-replacement.65138/post-816535

I'm in similar situation where I'm about to drop $170 each on 4 x lead-acid batteries to keep my existing setup functional. I wanted to consider removing the existing _backup_ setup and just doing a simple 12V SUMP, 100-200A LiFePO4 with Victron charger and pump controller.

What's not clear to me is if I can :

1. Simply connect the Victron Battery Charger to the LiFePO4 battery then from the 12V terminals that 12V backup SUMP controller and let the Victron keep the battery good-to-go. Of course I'd use Blue Sea terminal fuses and on/off switch disconnect. Can it be really this simple?
2. I'm unclear if I really need anything else from Victron to make this for for a high quality LiFeP04 setup. Do I need any sort of other BMS or control setups?

Thanks!

Being lazy and certainly knowing better I wanted easy..
I metered the power out of the Battery connection with and without the battery connected. The charger on the battery watch dog holds it at about 12.9V.

So I swapped in my Renogy Lifepo4 12v 100Ah and my Victron Charger.. Charger charges up to 100% and lets it drop down to 96-97%. then pulls it back up to 100%. My biggest concern was holding the battery at or near 100%. My research says although not ideal it does not drastically impact the battery life. The renogy on my sump is now in my trailer and still good to 99.9Ah (as per the renogy bluetooth) after 6 months of near 100%.

If you are really worried about it program the victron charger to may 13.3V. I did not want to sacrifice capacity in the event that I need it though.

So I have no switch and no fuse on the the battery. Maybe I will be smarter about it in the fall when it goes back in.

 

[French_guy]

Being lazy and certainly knowing better I wanted easy..
I metered the power out of the Battery connection with and without the battery connected. The charger on the battery watch dog holds it at about 12.9V.

So I swapped in my Renogy Lifepo4 12v 100Ah and my Victron Charger.. Charger charges up to 100% and lets it drop down to 96-97%. then pulls it back up to 100%. My biggest concern was holding the battery at or near 100%. My research says although not ideal it does not drastically impact the battery life. The renogy on my sump is now in my trailer and still good to 99.9Ah (as per the renogy bluetooth) after 6 months of near 100%.

If you are really worried about it program the victron charger to may 13.3V. I did not want to sacrifice capacity in the event that I need it though.

So I have no switch and no fuse on the the battery. Maybe I will be smarter about it in the fall when it goes back in.

Which Victron charger did you end up buying? you mentioned the IP65, but how many Amps ?

 

[bedpan]

Which Victron charger did you end up buying? you mentioned the IP65, but how many Amps ?

7amp

 

[bedpan]

Which Victron charger did you end up buying? you mentioned the IP65, but how many Amps ?

If I did it again I would buy a much larger one that can do double duty for charging other stuff

 

[AlexBen]

Hey folks. Not quite solar but mostly kinda related ;-)

I have a sump pump that runs quite a bit through Fall to Spring. 5 Years ago when I bought the house I put in a 12V battery backed up pump.

Hey, also unrelated but important.

Many people buy kits for the purpose of battery 12 V back up pumps and miss out on an important detail.

The 110 pump you have which is 1/4, 1/3, 1/2 or rarely full Hp rated has WAY more flow rate for 8-10 feet down from where it’s trying to dump the water. The usually tiny 12 pumps in most kits can’t come close to those rates, and even if your battery lasts a while, full time pumping of the 12V pump may not keep your pit empty.

You can buy 12V Bilge pumps for boats with far better specs that might have a chance at keeping you dry in heavy rain.

Sure it will use more current, but it will have a better chance at keeping pit empty.

During a heavy bad storm, while you have electricity, you may want to see if that tiny cheap 12V pump can even keep up.