diy solar

diy solar

Building a DIY Lifepo4 charger

if it is practical especially if you wanted to be able to adjust the settings and add features found in many charge controllers or chargers already integrated in many inverters.
I was looking for a 200V140A switching power supply and actually found one. But then realized that if I bought it I would end up in a huge fight with my wife. i.e. far too expensive ;(
 
Just as a note, I charge my batteries with the all-in-one inverter/charger. From a generator.
Not very often but last night I did, we haven't seen any sun for a while.
It does 20A (at 24V), and the fans are more on than off. Good thing it's outside :·)
.
 
But then realized that if I bought it I would end up in a huge fight with my wife. i.e. far too expensive ;(
There is a concept that says you can pay me now or you can pay more later. I don't know your skill set with regard to domestic relations or electronics but it's your choice. As others have said if you ruin your batteries you will have a bigger domestic relations problem. It is a risk management decision.
 
can you please rephrase? I am not sure I follow yet
You have admitted that you do not have the skill set. Therefore it is likely you will make mistakes that will cost you more to fix your mistakes than the original cost of the charger. Sweeping it under the carpet may solve your domestic relations problem but is not the optimal decision.
 
A typical automotive heavy-duty battery charger, like you find in car repair shops, usually looks something like this and costs some 300- 600 € depending on amps. Say 300 for 50A.
You might find a used one.
charger.png
 
Perhaps you could spend some time optimizing what you actually need.
I'll add some context. I should have lead with that I realize now.

I have recently gotten 16 3.2v 280A cells and I am planning to get a whole s$&tload more.

I think I need a battery bank that is quite potent as to make sure I do not get surprised again (like what we had just now with version 19 of our beloved virus friend) ever. And not be able to run my home and make sure my family does not notice anything is wrong in terms of comfort in our home.

Since I am a cheap ass and need to learn how to DIY I bought my very first 16 cells from our friends in the east. Shady at best so I need to quickly be able to test them.

Not only that, I plan to buy many more of cells. Maybe even enough to get to 400V (125S) if there is an actual use case for it.

What I think I need is a way to as quickly as possible test cells/packs of cells.

If I am not mistaken that means getting up to 3.6525v as fast as possible. And then running a load at 1C (280A)

THe source I have gotten the cells from is not known, only the go between (aliexpress). And many of us have learned the hard way that ali is not our friend when it comes to disputes. There is a narrow time margin between delivery and complaint hence my wish to go full force.
 
So you're planning to spend half of Liberia's GDP on cells and then save a hundred bucks on a charger? :rolleyes:
hahhaha I am not sure I can follow that yet ;( No I plan to make it feasible to go to insane(TM) levels step by step over time. IF I need to spend 8ke on a charger than 2 things will happen.
1) sleep in the garage because my wife has outcast me
2) I have learned nothing on how stuff actually works.

I am prepping for a storm that is even greater than V19
 
You guys input has set me on a different path. I will try and find a 0-400v variac and see if I can reason that.

Would that make for
variac -> fbr -> cell(s)?
 
Nailed the transformer part in the meantime.

According to an excerpt of a research paper I do not have to worry about the DC ripple after rectifying


Does anyone know research that shows the contrary?
 
Btw, when charging a single cell, or cells in parallel at 125 amps. The amps will go down to 0(.0001) amps once cell(s) are at the charge voltage yes?
 
Btw, when charging a single cell, or cells in parallel at 125 amps. The amps will go down to 0(.0001) amps once cell(s) are at the charge voltage yes?
Most battery chargers behave the same way. The charger tapers off the current in order to maintain the constant voltage. It doesn't matter if the cells are parallel or in series.
 
I will be using a DIY power transformer to charge the cell(s).

I am a little worried though that things go wrong because I missed something. So I am really hoping that the amps will reduce as the cell(s) reach their target voltage. Can anyone confirm?
 
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