Adding Eve cells to existing set up (not done by me)?

[ozma]

Hi all!

I currently have a bank of 4 Eve LiFePO4 cells, making it 305aH. I need more storage and am trying to figure out if I should buy more cells and add to this existing one - or just get a brand name battery. I'd feel more successful if I do the add-on method, but I really don't know where to start.

• Do I need to discharge the current batteries? Or will I charge the new and the old to float before connecting them?
• Is it best to disconnect the existing batteries while they're balancing in preparation for the new ones?
• Is there a limit to how many cells I can connect?
• The person who installed the existing batteries connected them in series, what is the reasoning for this vs. parallel?
• Is it just going to be easier on my brain to get a Renology (or other brand) LiFePO4 battery and can that connect to the DIY build?

Any help on how to get started on adding this storage would be of great help... Any pro van builders in my area don't seem to want to touch this DIY battery build to help me out. I'd also be super open to a video consult to help me work through this.

Thanks,

Corrina

 

[JJJJ]

Looks like you currently have a 12v battery. Typically Eve cells at that level are 304.

Series allows the voltage to add up. 4 cells 12v, 8 cells 24v etc.

A common question at this point is what are you trying to do with your batteries?

 

[ozma]

Looks like you currently have a 12v battery. Typically Eve cells at that level are 304.

Series allows the voltage to add up. 4 cells 12v, 8 cells 24v etc.

A common question at this point is what are you trying to do with your batteries?

Currently, it's running 2 Dometic CRX refrigerators, occasional use of Espar D2 heater, lights, a water pump, MaxxAir fan, and the 1000W inverter will be used for charging my phone, laptop, and the addition of battery is needed to run Starlink.

Does this answer your question properly?

 

[JJJJ]

Please forgive my question. Are you powering 12v appliances?

 

[Partimewages]

You need to figure your watts loads and run time for a 24 hour period. Then you can appropriately size your battery bank.

 

[ozma]

Please forgive my question. Are you powering 12v appliances?

Yes, these are the 12V appliances that are running straight from the battery: 2 Dometic CRX refrigerators, occasional use of Espar D2 heater, lights, a water pump, MaxxAir fan

And for those that are not (computer, phone, Starlink), I've got an inverter connected.

 

[ozma]

You need to figure your watts loads and run time for a 24 hour period. Then you can appropriately size your battery bank.

Using this online calculator, seems like at most, I'd be using 1748 Watt-hours/day.

I know I need to make a spreadsheet with more accurate Wh usage, but I think this is a good estimate.

 

[JJJJ]

As indicated above determining your needs is the best place to start. Considering that you are powering 12v appliances then staying at 12v may be simpler.

Having said that there are a number of things to consider. Are you hoping to learn how to DIY your own batteries? If so there are quite a few threads and videos that are available.

There are also prebuilt batteries that are available. I will defer to others for recommendations.

The third is space. If you determine more capacity is needed what can you safely place in the given space?

 

[Partimewages]

Don't forget inverter idle power. Some inverters are quite a load.