Old and New: I Need to Mix - How Old is Old??

[Matrix]

Ok, so I have 4 Trojan L16H-AC 435 ah batteries and a 24v system. I want to upgrade to a 48v system. I can sell my inverter ... but the batteries would be harder to market and ship. It would be easier and probably more cost effective just to add 4 more batteries like what I already have.

My existing batteries have been in service since Oct 16, 2017, or about 4 months. They have about 70-100 cycles depending on how you calculate DOD. I typically never discharge lower than 65% SOC and more typically 70% SOC. 3-5 times I have discharged to 55% SOC.

If I wanted to add to these batteries 4 more just like them, Would it be best too ...

1. Simply purchase more and connect them up in series?

Or

2. Purchase 4 more ... Put the older ones on a float charger fully charged, and then cycle the new ones at 24v for about 4 months before connecting all 8 together and purchasing a 48v inverter?

Is there some option I am missing?

[Matrix]

Any Thoughts?

[SunEagle]

Any Thoughts?

As previously posted adding new batteries to an old set can end up reducing the life span of the new batteries.

With that said it is hard to define what an "old" battery is based on the combination of age, cycles it has seen and DOD of those cycles.

Since you are very aware of how your existing batteries have performed you would also be the best to see if the "new" set is working as expected or are not charging as they should.

But as some of us say "if you can handle the cost then sometimes experimenting with battery systems is worth the risk".

Besides who hasn't killed off their first battery system getting to understand the technology along with it's performance.

[Matrix]

OK thanks. So mostly it's see how they do.

[SunEagle]

OK thanks. So mostly it's see how they do.

I would wire them into a 48v system and see how they work out. IMO the existing batteries are still good unless you somehow went below 50% SOC a couple of times.

[travissand]

Maybe you could experiment with getting three of those battery balancers. Get two of the 4-port balancers and one of the two port balancers. That way the two four ports could be on the two different aged sets and then the 2-port could connect those two sets together. They're good for 10 amps and it seems to me that this would alleviate your concern. If it works out you could buy me a beer or send me your old inverter lol and I can combine it up to my SW4024.

[travissand]

Here's a link to the battery balancer that I'm trying to order. They've got a 2 cell version as well and they seem to have decent reviews. https://www.amazon.com/Battery-Equal.../dp/B01JJ4X8CO

[PNW_Steve]

Here's a link to the battery balancer that I'm trying to order. They've got a 2 cell version as well and they seem to have decent reviews. https://www.amazon.com/Battery-Equal.../dp/B01JJ4X8CO

That has my attention.....

The online description makes it sound like the best thing since sliced bread. Is it real or "snake oil" ?

[travissand]

Is it real or "snake oil" ?

Check out this companies sales pitch on balancing lead acids. There product cost a lot more though.

https://youtu.be/d7bIwEB3iWk

[PNW_Steve]

Check out this companies sales pitch on balancing lead acids. There product cost a lot more though.

https://youtu.be/d7bIwEB3iWk

Question remains... Is it real or snake oil?

I see a number of products out there that claim great benefit. Many of them are engineered to separate a fool from his money.

Is this a good solution or a waste of money?

[travissand]

Question remains... Is it real or snake oil?

I see a number of products out there that claim great benefit. Many of them are engineered to separate a fool from his money.

Is this a good solution or a waste of money?

well I'm ordering three or four sets of the cheaper one if I remember I can give you an update in a few months. Judging by the reviews and I've read many in a lot of different areas the cheaper one does work but some people don't like that it's noisy

[Matrix]

I stayed series and in series battery balancers are not needed if the cabling is good