Battery wiring configuration

[MAG]

We are changing from 4 AGM 6 volt batteries to 2 Trojan T105 6 volt batteries.  We would rather have technical help with this, but the trailer repair shops are running 45 days behind on battery issues.

So  a question about how to connect the new batteries…… would this be appropriate:  For the cables that come from inside the Ollie to the battery tray….Copy the wiring pattern from the 4 battery configuration:  for  the positive on one battery  connect the solar 2 color cable,  and the red cable from the converter.  For the negative on the other battery  connect the temperature sensor,  and the yellow ground cable).  Then, on the posts not used for these, add a cross-cable from negative to positive between the two batteries. 

Thanks so much for your help.

[SeaDawg]

Someone, likely @ScubaRx, will step in on specifics. 

Do you usually camp with hookups? You do realize with only 2 x 6v, vs 4 x 6v batteries ,  you're cutting your power storage in half?

You may also likely have to make changes to your battery charging, going from agm to lead acid. 

[MAG]

Thanks for the thoughts SeaDawg….

Last year in a number of posts, folks helped us as we tried to understand why our previous batteries failed (melted, cooked).  We have not been able to determine with certainty what the problem was……So, we plan to see how we do with 2 batteries (they are AGMs) for now, rather than risk ruining even more batteries.  It’s been  expensive and frustrating to get to where we are.  

[John E Davies]

If this is a test scenario, why not just install one cheaper 12 volt sealed lead acid DEEP CYCLE battery from Walmart? You can always sell it later on Craigslist,

https://www.walmart.com/ip/Mighty-Max-12V-100AH-Battery-for-Solar-Wind-Deep-Cycle-VRLA-12V-24V-48V/179446910?athbdg=L1600&from=/c/[...seo]

T105s are way way more labor intensive to maintain and they vent corrosive and explosive gases. You are taking a huge step backwards going from AGMs. I don’t recommend it.

John Davies

Spokane WA

[MAG]

Hi John, I am so sorry for the miscommunication.  I have great respect for your expertise, and that of the other wonderful folks on this forum who have been so helpful to us.  

 The batteries we recently bought are AGMs….. Trojan T105 AGMs.  We used these batteries for 7 years with good luck, before our problems started.  They were the original equipment when we bought our Ollie.

 

 

[ScubaRx]

On 5/15/2023 at 11:53 AM, MAG said:

Hi John, I am so sorry for the miscommunication.  I have great respect for your expertise, and that of the other wonderful folks on this forum who have been so helpful to us.  

 The batteries we recently bought are AGMs….. Trojan T105 AGMs.  We used these batteries for 7 years with good luck, before our problems started.  They were the original equipment when we bought our Ollie.

 

 

Trojan T105’s are not AGM’s. They are flooded lead acid that must be meticulously maintained (checking specific gravity, adding water, if needed) for you to get the maximum life out of them. AGM’s, on the other hand, are still flooded lead acid, but you are unable to add water to them, as they are sealed, and the acid is absorbed in a glass mat. AGM’s. require much less maintenance and we got seven years out of our first set before changing to three Battle Born Lithium‘s. AGM’s can still vent hydrogen gas if they are overcharged. The biggest downside to this is you can’t replace the liquid that is boiled off.

[SeaDawg]

Well, my bad.

On 5/15/2023 at 12:53 PM, MAG said:

The batteries we recently bought are AGMs….. Trojan T105 AGMs.  

I thought all Trojan t105s were flooded, not agm, but, apparently,  trojan has been selling t105-agm versions, also, for some period of time.

I certainly have no idea if your original t105 batteries were agm, or not, but it is possible that the ones you recently acquired are agm_sealed. Please make sure your charging profile is set for agm, not flooded, if that's what you got. Likely $300 each, from what I've seen. 

(I always thought Oliver installed Flooded lead acid t105's ... ☹️)

[MAG]

Yes, the batteries we bought are the one SeaDawg shows, the T105 AGM.  Maybe we will regret it, I don’t know. 

 We’re being careful:  Last year we  sent our Blue Sky controller to the manufacturer, it checked out perfect.  A technician at Progressive Dynamics told us  to check the  converter output before installing batteries; we did, it’s perfect at 13.6 V.  The solar panels are covered, for when we install the batteries.  Blue Sky gave us the new inputs for this battery for the solar controller, so we are ready to do that once the batteries are installed, which we plan to do when we get back from a family reunion.  If we are certain about how to configure the battery cables.

 

Thanks for your help.

[MAG]

Question for you @ScubaRx:  Is this the appropriate wiring configuration for installing these batteries?

Thank you for your help.