2 add or not 2 add?

I currently have 10 - Everstart Maxx 29dc batteries in parallel that has been powering our living space (rv) and tools through an Everstart Maxx 1500 inverter. It has been 9 months on this setup and just got in my 48v 3000w pure sine wave inverter in an effort to upgrade our system in small steps. I'm short 2 batteries from going 48v and putting this more efficient inverter in play, but want to know what's the worst case scenario that can result from me adding 2 new batteries to the old bank?

In general, to add newer identical lead acid batteries (mixing unidentical batteries is not a good idea) to an older battery bank would reduce the life of the new batteries. You can consider them the same age as the older ones.

myersfamilyhome said:

I currently have 10 - Everstart Maxx 29dc batteries in parallel that has been powering our living space (rv) and tools through an Everstart Maxx 1500 inverter. It has been 9 months on this setup and just got in my 48v 3000w pure sine wave inverter in an effort to upgrade our system in small steps. I'm short 2 batteries from going 48v and putting this more efficient inverter in play, but want to know what's the worst case scenario that can result from me adding 2 new batteries to the old bank?

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Your 10 Walmart batteries are car starting batteries that are not designed for deep discharge.
How deeply are you cycling them?
Is your plan to destroy them then use the 2 year warranty?

How many watts solar panels do you have for your Epever 80A SCC?

Forbisher said:

Your 10 Walmart batteries are car starting batteries that are not designed for deep discharge.
How deeply are you cycling them?
Is your plan to destroy them then use the 3 year warranty?

How many watts solar panels do you have for your Epever 80A SCC?

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The 29dc are deep cycle and have been used by others for there solar. Not any different than any other use of LA deep cycle batteries from other companies.

myersfamilyhome said:

The 29dc are deep cycle and have been used by others for there solar. Not any different than any other use of LA deep cycle batteries from other companies.

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Let me correct, not any different than any other batteries of this chemistry and design. The reason for going this route was availability at the time. I'm averaging 90ah from each without issue and they are holding up wonderfully. I intend to go LifePo4 but it is a larger investment initially which I cannot afford.

myersfamilyhome said:

The 29dc are deep cycle and have been used by others for there solar. Not any different than any other use of LA deep cycle batteries from other companies.

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The deep cycle lead acid batteries from Costco like golf cart batteries do not rate CCA.
You spent over $1000 on 10 12V batteries for how many Ah?

I would just add two additional and expect them to degrade to the same level as your current batteries. If it has been working for 9 months, I think you are good to go assuming you are just replacing the inverter for efficiency and not to add more draw.

Forbisher said:

The deep cycle lead acid batteries from Costco like golf cart batteries do not rate CCA.
You spent over $1000 on 10 12V batteries for how many Ah?

Robot or human?

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CCA specification on batteries does not dictate that it's not designed for use in other applications. If it only provided CCA then I would agree. Both motorhomes and boats use these batteries because they need the surge of power to turn a starter which cranks over the engine, the CCA defines the minimum amps needed at a cold state to meet these demands. If it's designed for a specific use then it is expected to meet the demands it's labeled for. In this case these batteries are labeled with CCA, DC, and AH. It is designed for deep cycle use, can meet the demands of vehicles that need the specified CCA to start them, and it's been rated at providing the specified AH.

Though the batteries are rated at 122ah I estimate they are closer to 100ah. My price on them is approx. $125-135 and that includes the core charge. So at 50% utilization I'm paying about $2.70pah. The value this provides me is convenience of replacement when something goes wrong. I live in the mountains offgrid and walmart is 5 hrs away and that's in a small town with no solar resources. I have a planned order of individual LiFePo4 cells to build myself but purchasing in the states is still way too expensive so waiting until funds are available to place a large order to meet my needs. Until then adding the little more power I need to improve my quality of life is worth it for me. When you look at a battery remember that the specifications are listed to define what it's designed for, all specifications on it, not just the first one you read.

iamrich said:

I would just add two additional and expect them to degrade to the same level as your current batteries. If it has been working for 9 months, I think you are good to go assuming you are just replacing the inverter for efficiency and not to add more draw.

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Thanks for your feedback, I was aware of this already but never hurts to double triple check with others to make sure there's not something your overlooking. Ignorance and arrogance gets you in trouble lol. Both of your responses confirms that I'm only getting hit in the life of my new batteries and as an added bonus I can add the additional panels that I wasn't able to use on the 12v configuration.

Yeah, if the old batteries fail you are basically out the cost of the new ones. If they last until new LiFePo setup is ready, then it was money well spent to let you take advantage of the new inverter now, instead of having to wait. You should be able to wire everything up and then just switch over to the new batteries when they are ready (you will have to change the charging settings of course).

Yeah I just got in my smart shunt and looking forward to getting down to the details of usage and where I can optimize everything before I get my cells ordered. Since I'm offgrid LTO is a serious consideration. Once purchased I would expect it to outlive me ha ha

myersfamilyhome said:

Yeah I just got in my smart shunt and looking forward to getting down to the details of usage and where I can optimize everything before I get my cells ordered. Since I'm offgrid LTO is a serious consideration. Once purchased I would expect it to outlive me ha ha

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hello what batteries are you getting ? i am in thesame way using walmart battery everstart 29dc MAXX 2 year free replacement i have 24 pcs 3 banks of 48volt ..you said LTO do you have the link ?