Powering AGM batteries

[frankz66]

Hello everyone, I wanted to ask if there is a solution to be able to charge AGM batteries with a current regulator.

Let me explain :

I am currently using a 4 kw AGM 12v storage, which I would like to replace with a single 300 A 12.8 volt lifepo4 battery. In order to use the old storage, still new and working, I was thinking of buying a solar charger to connect to the electricity produced by my system. That is, the scenario would be that my epever charges the lifepo4, in the meantime from the reverse as well as powering the house, I could connect a battery charger for the AGMs and then I don't know how, to be able to make the switch when I need the AGMs. My request might seem stupid in the eyes of many competent users, but they are still at the first experiences. Thank you

 

[timselectric]

The charging profiles of LiFePo4 and AGM are very similar. Close enough that you can just parallel them together. Because the LiFePo4 charge/ discharge curve is so flat, they will do most of the work. And the AGM's will be the reserve capacity. This can extend the life of both. Because the LiFePo4 will spend less time in the lower part of its curve. And the AGM's will be cycling a lot less.

 

[SamDeleted]

The charging profiles of LiFePo4 and AGM are very similar. Close enough that you can just parallel them together. Because the LiFePo4 charge/ discharge curve is so flat, they will do most of the work. And the AGM's will be the reserve capacity. This can extend the life of both. Because the LiFePo4 will spend less time in the lower part of its curve. And the AGM's will be cycling a lot less.

Do you have to match the capacities of the AGM and the lifepo4 ?

 

[timselectric]

Do you have to match the capacities of the AGM and the lifepo4 ?

No

 

[SamDeleted]

No

Hybrid Battery Bank – Introduction – Wildebus Home

www.wildebus.com

Apparently there are some issues with charging especially long drawn out floats of AGM , they use a relay and a shunt to disconnect the Lithium

 

[SamDeleted]

Hybrid Battery Bank – Charging – Wildebus

www.wildebus.com

 

[frankz66]

Then what I meant was just the possibility of being able to connect the batteries of the old storage with a 220 V charger. The new batteries will only be connected exclusively to the controller and for the old storage it will be charged by the charger in 220 V and through a switch only at night I will have to have the possibility to have the spare batteries that are the agm

 

[timselectric]

Hybrid Battery Bank – Introduction – Wildebus Home

www.wildebus.com

Apparently there are some issues with charging especially long drawn out floats of AGM , they use a relay and a shunt to disconnect the Lithium

I don't see any issue with floating.
My battery bank is full by 11am. And floats for the rest of the day. I wouldn't want it floating for multiple days. But it's cycled daily. So, this isn't a problem.

 

[timselectric]

Then what I meant was just the possibility of being able to connect the batteries of the old storage with a 220 V charger. The new batteries will only be connected exclusively to the controller and for the old storage it will be charged by the charger in 220 V and through a switch only at night I will have to have the possibility to have the spare batteries that are the agm

Doable, but a lot less efficient.
And then you have to manually control which batteries you are drawing from.