Bank of four 22ah Batteries Feedback? (1 Viewer)

[TheGrrrrr]

Anyone either considered or actually tried something like a bank of 3 or 4 of these 22ah batteries mounted up against the forward face of a drawer system?

Amazon product ASIN B01JNZ16SW
With dimensions: 7.13 inches long x 3.01 inches deep x 6.57 inches tall. I believe they would fit between the second row and the drawers. Wired as a 12v bank and managed from a RedArc BCDC, I'm thinking they could be a really decent option and only about $240 for 4 batteries. Seems like a good use of otherwise wasted space and a good location for heavy batteries. Also wondering if having the ability to swap out batteries as they fail versus losing one big battery is an advantage or a disadvantage?

Can anyone think of a good reason why they wouldn't work or be a good option? Automotive electrical is not my area of expertise.

 

[TheGrrrrr]

Obviously my drawings are hilariously bad, but this is what I am thinking... (sadly no Visio for Mac)

 

[Sandroad]

There is no particular problem with banks of batteries. I use several batteries in banks in various solar applications all the time. However, it does add complexity and in my experience if one battery goes bad, it takes all of them down with it because lead-acid batteries of all construction types do not like to be fully discharged (or really more than about 50%) discharged). I don't recommend using the specific battery you linked, because it's a gel battery (even through it also says AGM on the side). I quoted below from a source about deep cycle batteries I trust that disparages gel batteries. Spend some time on the site I linked below and see if you can find a better battery that fits your space. Remember that you only get about 1/2 the stated amp-hours out of lead-acid batteries and you get almost all the stated amp-hours out of lithium. And finally for now, keep in mind you have to protect all thone connection from short-circuits with some kind of cover or box. So, maybe lithium would work best for your application, albeit with much higher cost.

"Gelled batteries, or "Gel Cells" contain acid that has been "gelled" by the addition of Silica Gel, turning the acid into a solid mass that looks like gooey Jell-O. The advantage of these batteries is that it is impossible to spill acid even if they are broken. However, there are several disadvantages. One is that they must be charged at a slower rate (C/20) to prevent excess gas from damaging the cells. They cannot be fast charged on a conventional automotive charger or they may be permanently damaged. This is not usually a problem with solar electric systems, but if an auxiliary generator or inverter bulk charger is used, current must be limited to the manufacturers specifications. Most better inverters commonly used in solar electric systems can be set to limit charging current to the batteries.

Some other disadvantages of gel cells is that they must be charged at a lower voltage (2/10th's less) than flooded or AGM batteries. If overcharged, voids can develop in the gel which will never heal, causing a loss in battery capacity. In hot climates, water loss can be enough over 2-4 years to cause premature battery death. It is for this and other reasons that we no longer sell any of the gelled cells except for replacement use. The newer AGM (absorbed glass mat) batteries have all the advantages (and then some) of gelled, with none of the disadvantages."

Deep Cycle Batteries - Batteries & Battery Storage - Residential | NAZ Solar Electric

We stock a wide variety of deep cycle batteries. We carry flooded, industrial (forklift type) sealed AGM, Lithium, and standard deep cycle batteries. Any purchase from us includes technical support for the life of the system. Buy with confidence.

www.solar-electric.com

 

[TheGrrrrr]

There is no particular problem with banks of batteries. I use several batteries in banks in various solar applications all the time. However, it does add complexity and in my experience if one battery goes bad, it takes all of them down with it because lead-acid batteries of all construction types do not like to be fully discharged (or really more than about 50%) discharged). I don't recommend using the specific battery you linked, because it's a gel battery (even through it also says AGM on the side). I quoted below from a source about deep cycle batteries I trust that disparages get batteries. Spend some time on the site I linked below and see if you can find a better battery that fits your space. Remember that you only get about 1/2 the stated amp-hours out of lead-acid batteries and you get almost all the stated amp-hours out to lithium. And finally for now, keep in mind you have to protect all this connection from short-circuits with some kind of cover or box. So, maybe lithium would work best for your application, albeit with much higher cost.

"Gelled batteries, or "Gel Cells" contain acid that has been "gelled" by the addition of Silica Gel, turning the acid into a solid mass that looks like gooey Jell-O. The advantage of these batteries is that it is impossible to spill acid even if they are broken. However, there are several disadvantages. One is that they must be charged at a slower rate (C/20) to prevent excess gas from damaging the cells. They cannot be fast charged on a conventional automotive charger or they may be permanently damaged. This is not usually a problem with solar electric systems, but if an auxiliary generator or inverter bulk charger is used, current must be limited to the manufacturers specifications. Most better inverters commonly used in solar electric systems can be set to limit charging current to the batteries.

Some other disadvantages of gel cells is that they must be charged at a lower voltage (2/10th's less) than flooded or AGM batteries. If overcharged, voids can develop in the gel which will never heal, causing a loss in battery capacity. In hot climates, water loss can be enough over 2-4 years to cause premature battery death. It is for this and other reasons that we no longer sell any of the gelled cells except for replacement use. The newer AGM (absorbed glass mat) batteries have all the advantages (and then some) of gelled, with none of the disadvantages."

Deep Cycle Batteries - Batteries & Battery Storage - Residential | NAZ Solar Electric

We stock a wide variety of deep cycle batteries. We carry flooded, industrial (forklift type) sealed AGM, Lithium, and standard deep cycle batteries. Any purchase from us includes technical support for the life of the system. Buy with confidence.

www.solar-electric.com

Excellent info. Thank you. It sounds like my rough design idea is feasible, but I need to find a better battery. I'm wondering how the RedArc would factor into the charging concerns? Know of anyone that builds custom form-factor batteries?

Could 3 or 4 of these be daisy-chained together?

Custom LFP Flat Battery Pack: 12.8V 26.4Ah (337Wh 40A Rate) (31.68)

6848

www.batteryspace.com

 

[Sandroad]

Nope, no custom builders out there (at least at any affordable cost). From what I've read on here, the RedArc would do fine with a variety of battery charging needs, but I've no direct experience with one. So long as they are all the same brand/model/age/Ah, a bank acts as one battery as far as charging is concerned. There are some practical limits, because if your bank is too large, there is the likelihood they would not get fully charged. Your 88Ah example is fine. I'll bet you can find an AGM or LiFePo4 battery in an appropriate size.

 

[tincan45]

With regard to the LFP batteries, make sure you know both charge and discharge profiles. Before you select a battery you also need to ask yourself a few questions:

How many amps do you plan on pulling from your pack?
How fast do you plan on charging it?
How long do I need it to run?
What temperatures will I be charging and discharging?

Once you know this information, it's a lot easier to pick a battery/charger that meet your requirements.

 

[catastrofe]

Lots of good battery info here (not just solar): DIY Solar Power Forum

 

[indycole]

I believe that you'd want to connect the positive from the Redarc to the first in the battery bank rather than the last (basically, opposite of the ground).

 

[catastrofe]

Anyone either considered or actually tried something like a bank of 3 or 4 of these 22ah batteries mounted up against the forward face of a drawer system?

Amazon product ASIN B01JNZ16SW
With dimensions: 7.13 inches long x 3.01 inches deep x 6.57 inches tall. I believe they would fit between the second row and the drawers. Wired as a 12v bank and managed from a RedArc BCDC, I'm thinking they could be a really decent option and only about $240 for 4 batteries. Seems like a good use of otherwise wasted space and a good location for heavy batteries. Also wondering if having the ability to swap out batteries as they fail versus losing one big battery is an advantage or a disadvantage?

Can anyone think of a good reason why they wouldn't work or be a good option? Automotive electrical is not my area of expertise.

If you haven't purchased your BCDC yet, check out OK4WD. They had the best price on a BCDC1240D, free shipping, and you can find a 5% discount code floating around the internet.

 

[TheGrrrrr]

After a lot of reading (most of which I think I understood) I'm thinking I may now go with somethings like this:

Amazon product ASIN B078JB836N
If it doesn't fit between the drawers and the 2nd row, then it will just have to go inside one of the wings. Any disadvantage to running 4 lower voltage batteries in parallel to make up the bank?

At $550 its not that much more than a high-end 100ah AGM, gets better usage of the AHs and more cycles than the AGM in much less space/weight (fitting in a tight spot is the whole point of this exercise). Seems like the benefits are a good value for the cost difference. This is where the community continues to help me by telling me why I'm wrong... ... which is the whole point of this thread and DEEPLY APPRECIATED! Seriously, I couldn't figure any of this stuff out without you all.

 

[TeCKis300]

What is it that you intend the batteries to run?

There's potentially more than just a charger and battery you need to consider. To have a good working and safe setup, you'll want something to manage the overall workings of the battery including discharge to avoid damage.

I'd highly encourage you to look into a battery management system (BMS). It's generally advisable to use one with these types of packs to manage low/high voltages, low/high temps, and potential shorts.

 

[Kurosawa]

After a lot of reading (most of which I think I understood) I'm thinking I may now go with somethings like this:

Amazon product ASIN B078JB836N
If it doesn't fit between the drawers and the 2nd row, then it will just have to go inside one of the wings. Any disadvantage to running 4 lower voltage batteries in parallel to make up the bank?

At $550 its not that much more than a high-end 100ah AGM, gets better usage of the AHs and more cycles than the AGM in much less space/weight (fitting in a tight spot is the whole point of this exercise). Seems like the benefits are a good value for the cost difference. This is where the community continues to help me by telling me why I'm wrong... ... which is the whole point of this thread and DEEPLY APPRECIATED! Seriously, I couldn't figure any of this stuff out without you all.

I've thought about this location for some DIY lithium cells as well. I mounted my fuse box and solar charge controller there and thought a Red Arc Manager 30 and a creative house battery could potentially fit. I loosely started adding it up in my head however and realized there was no way I could justify the money it would take to do it really well. At least not at the moment, since my electrical needs are low enough to be solved more cheaply in other ways.

I really do like the idea though and I'd love to see you detail it if you take it on.

 

[TheGrrrrr]

What is it that you intend the batteries to run?

There's potentially more than just a charger and battery you need to consider. To have a good working and safe setup, you'll want something to manage the overall workings of the battery including discharge to avoid damage.

I'd highly encourage you to look into a battery management system (BMS). It's generally advisable to use one with these types of packs to manage low/high voltages, low/high temps, and potential shorts.

Is there a BMS that you would recommend? Would it go between the battery bank and the fuse block?

My understanding is the the power would flow like this:

Starting Battery/Alternator/Solar ---> RedArc BCDC ---> Battery (Bank) ---> BMS ---> Fuse Block ---> Powered Accessories (USB ports, 12v Ports, Inverter, Fridge, Camp Lighting, etc.)

Is that correct?

 

[tincan45]

Is there a BMS that you would recommend? Would it go between the battery bank and the fuse block?

My understanding is the the power would flow like this:

Starting Battery/Alternator/Solar ---> RedArc BCDC ---> Battery (Bank) ---> BMS ---> Fuse Block ---> Powered Accessories (USB ports, 12v Ports, Inverter, Fridge, Camp Lighting, etc.)

Is that correct?

Here's my basic schematic...I'm using victron products, but the design doesn't really change. You can use redarc in exactly the same way. I'm also building a custom battery to fit in the confines of my drawer system. Just be sure you build in the appropriate battery and circuit protection. Planing is key to a solid DC system.

 

[TheGrrrrr]

Here's my basic schematic...I'm using victron products, but the design doesn't really change. You can use redarc in exactly the same way. I'm also building a custom battery to fit in the confines of my drawer system. Just be sure you build in the appropriate battery and circuit protection. Planing is key to a solid DC system.

If that's basic, I may be in over my head. I guess it's time for more reading for me.

 

[Sandroad]

After a lot of reading (most of which I think I understood) I'm thinking I may now go with somethings like this:

Amazon product ASIN B078JB836N
If it doesn't fit between the drawers and the 2nd row, then it will just have to go inside one of the wings. Any disadvantage to running 4 lower voltage batteries in parallel to make up the bank?

At $550 its not that much more than a high-end 100ah AGM, gets better usage of the AHs and more cycles than the AGM in much less space/weight (fitting in a tight spot is the whole point of this exercise). Seems like the benefits are a good value for the cost difference. This is where the community continues to help me by telling me why I'm wrong... ... which is the whole point of this thread and DEEPLY APPRECIATED! Seriously, I couldn't figure any of this stuff out without you all.

You probably know this, but those batteries in the link in your post #10 are in series, not parallel. Series connections go from negative to positive between batteries and increase the voltage but not the Ah. Parallel connections go from positive to positive and negative to negative between batteries and increase the Ah but not the voltage. Super good advice from others so far.....you’ve come to the right place. And, I second the necessity of using a battery management system if you go with your linked example In post 10. The Battle Born LiFePo4 batteries I use have a built in BMS and it’s essential for safety.

 

[tincan45]

If that's basic, I may be in over my head. I guess it's time for more reading for me.

Ha! Doing it, and doing it correctly are two separate things. Anyone can throw in a battery and a charger. Get familiar with the fundamentals of DC systems and it won't seem so complex. It's worth the time, and will probably save you some headache in the future. Also, there is an entire section for all this on MUD as well. Since this isn't unique to the 200 series, you might get more information there.

Power Systems

Solar, lithium or AGM batteries, wind, generators, etc.

forum.ih8mud.com

 

[abuck99]

Fwiw LiFePO batteries dont perform well in cold temps <32F
There are few different types- read up before pulling the trigger

 

[tincan45]

Fwiw LiFePO batteries dont perform well in cold temps <32F

They mostly don't charge well. You can discharge at lower temps (-10 to -20 C). Something good to know, when you do get stuck in cold weather. If you discharge at high load it will warm the batteries to a point there they can be safely charged.

A good everyday example of this is my field laptop. It had been in my truck overnight in sub freezing temps. I killed the charging circuit by plugging in the charger immediately. Charging cold lithium is bad! I still tend to forget and leave my laptop in the truck occasionally, but now that I know to turn it on and let it "warm up" before charging and I've been fine. Granted, lithium-ion is different chemistry than LFP, but the same principals apply.

 

[cboyd]

Checkout will prowse in YouTube. He tests all of thes 100ah Lithium’s and has BMS testes too.

you cannot charge below 32 or you’ll kill them permanentl. The manager30 from redarc knows this, not sure about the BCDC. I’m thinking of a similar project.