diy solar

diy solar

Just purchased 4 BATTERY HOOKUP 3.2V 100ah MODULES

@j8j and others who have used these in a high vibration environment like an RV are they working well? Anything you would do differently?

My existing Flooded Lead Acids will no longer take a charge - honestly not upset about that - so I am looking to go Lithium ? Would really like to get away from the limits of Lead Acid batts i.e. nonsense of refilling the lead acids with water, only being able to use half the capacity, insanely heavy etc.

Am I correct in thinking one Overkill BMS can monitor 4 packs for a total of 400Ah ? That sounds almost too simple. If it goes well I may add a 2nd bank of 4 more packs to really go nuts - I tend to go off grid for a couple days at a time and would like to NOT have the diesel genny running so much.

Would most likely match up to a Victron Multiplus
 
@j8j

Am I correct in thinking one Overkill BMS can monitor 4 packs for a total of 400Ah ? That sounds almost too simple. If it goes well I may add a 2nd bank of 4 more packs to really go nuts - I tend to go off grid for a couple days at a time and would like to NOT have the diesel genny running so much.

You'd want 4 "packs" equaling 16 "cells" - 4P4S them. 12v 400ah
 
@j8j and others who have used these in a high vibration environment like an RV are they working well? Anything you would do differently?

My existing Flooded Lead Acids will no longer take a charge - honestly not upset about that - so I am looking to go Lithium ? Would really like to get away from the limits of Lead Acid batts i.e. nonsense of refilling the lead acids with water, only being able to use half the capacity, insanely heavy etc.

Am I correct in thinking one Overkill BMS can monitor 4 packs for a total of 400Ah ? That sounds almost too simple. If it goes well I may add a 2nd bank of 4 more packs to really go nuts - I tend to go off grid for a couple days at a time and would like to NOT have the diesel genny running so much.

Would most likely match up to a Victron Multiplus
Assuming you’re talking about 12v you’d want 1 BMS for every 4 cells and that would create a 100 AH battery.
You could then combine 4 of those batteries in parallel for 400 AH.
 
Assuming you’re talking about 12v you’d want 1 BMS for every 4 cells and that would create a 100 AH battery.
You could then combine 4 of those batteries in parallel for 400 AH.
DogFather Keep in mind the BMS is current limited. Even with 400ah available you can only draw what the BMS will supply ( Overkill xiaoxiang is 120a @ 12v)
 
Just finished my 4s build with these packs. I think it came out pretty well. I ended up using an Apache 3800 case from Harbor Freight (Pelican knock off). The case feels very sturdy and includes foam which I used to pack around the cell packs, I don't think they are moving around at all.

It's a pretty snug fit, you can see that I had to trim some of the egg crate type foam on the top of the case
51401201154_5fc26c26b4_b.jpg


I wrapped all the connections with mastic tape and then electrical tape over that. I used some heavy duty battery terminal posts from amazon at one corner of the case. If I was to do it again I'd probably use a heavy duty anderson plug I think but this should work fine.

Currently running a test to see how long it will power my fridge which will be what it's mostly used for as well as charging laptops and maybe the occasional heated blanket in cold temps.
51401201114_6445150d4a_b.jpg
 
I wonder how much these heat up during discharging at various rates. Those enclosures you guys are building have nothing in terms of ventilation or heat dissipation (except for the large metal case on the previous page)
 
If you think about any of the drop in replacement batteries they are fully sealed with no venting. I’ll never go over .2c and I tested at that, barely warm to the touch. At 1c I’d be more concerned maybe.

If there is a heat issue I’ll know about it, the JBD BMS I used has 3 temp sensors.
 
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Has anyone done more than a 2p battery with these? Looking at doing a 4s6p pack for 12V 600Ah for an RV's 12v system. also needs to fit in a relatively compact space so wondering what people have done for a larger number of packs in parallel. Im thinking some sort of aluminum busbar for the parallel connection between all the packs, allowing for 4 stacks of 6 laid on their side stacked on top of each other. Unfortunately the space i have to get them into along with the BMS's and battery monitor shunt is 11" wide x 20" tall x 23" long and take up as little space as possible to retain as much storage i can
 
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Just finished my 4s build with these packs. I think it came out pretty well. I ended up using an Apache 3800 case from Harbor Freight (Pelican knock off). The case feels very sturdy and includes foam which I used to pack around the cell packs, I don't think they are moving around at all.

It's a pretty snug fit, you can see that I had to trim some of the egg crate type foam on the top of the case
51401201154_5fc26c26b4_b.jpg


I wrapped all the connections with mastic tape and then electrical tape over that. I used some heavy duty battery terminal posts from amazon at one corner of the case. If I was to do it again I'd probably use a heavy duty anderson plug I think but this should work fine.

Currently running a test to see how long it will power my fridge which will be what it's mostly used for as well as charging laptops and maybe the occasional heated blanket in cold temps.
51401201114_6445150d4a_b.jpg
Nice setup. Those Ridgid toolboxes are the same ones I used for my larger solgen build. Large box for the batteries, medium box for the electronics and small box to store the cables. Will do a full write up post once complete.
Just finished my 4s build with these packs. I think it came out pretty well. I ended up using an Apache 3800 case from Harbor Freight (Pelican knock off). The case feels very sturdy and includes foam which I used to pack around the cell packs, I don't think they are moving around at all.

It's a pretty snug fit, you can see that I had to trim some of the egg crate type foam on the top of the case
51401201154_5fc26c26b4_b.jpg


I wrapped all the connections with mastic tape and then electrical tape over that. I used some heavy duty battery terminal posts from amazon at one corner of the case. If I was to do it again I'd probably use a heavy duty anderson plug I think but this should work fine.

Currently running a test to see how long it will power my fridge which will be what it's mostly used for as well as charging laptops and maybe the occasional heated blanket in cold temps.
51401201114_6445150d4a_b.jpg
Nice setup. Those Ridgid toolboxes are the same ones I'm using for my larger portable solgen build. Large box with wheels for the batteries, medium box for the electronics and small box to store the cables and all three secure together to wheel around. Will do a full write up post once fully complete.
 

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Nice setup. Those Ridgid toolboxes are the same ones I used for my larger solgen build. Large box for the batteries, medium box for the electronics and small box to store the cables. Will do a full write up post once complete.

Nice setup. Those Ridgid toolboxes are the same ones I'm using for my larger portable solgen build. Large box with wheels for the batteries, medium box for the electronics and small box to store the cables and all three secure together to wheel around. Will do a full write up post once fully complete.
lookin good!
 
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