Battery questions

[Mikemyday]

I have a (low budget) solar pwm controller, which (I read) behaves just a regular charger.
I got a sealed lead acid battery that I want to fully charge with the solar controller, before I use it in a live setup.
Could I just attach a regular power supply to the input of the controler, where you normally would attach the solar panel?
I would expect so, but want to double check.


The other question is about 18650 Li-ion charging.

I am considering to use a pack of 18650 batteries instead of sealed lead acid. Mostly because of size, but also to
experiment with.
Now, almost all solar controllers are meant for lead acid, so I can't just attach other battery types.
Would it be possible to connect a balancing board/BMS controller (TP4056 for example) to the battery output
or load output of the solar controller?
Not sure if the Solar controller expects to "see" a lead acid battery to the output and get confused somehow.

[Mike90250]

It won't bother many sturdy controllers at all. But you might want to do this outdoors, away from anything that would burn or that you value.
Generally, the solar controller is many times more powerful than what the BMS can manage, so you still burn your battery bank up,

[theojkett]

Hi kids,
I am a relatively new guy in the solar world. But, I have installed a 48V system on my off-grid cabin. However there was an issue.

I'll make it short. 48V system, 9 panels, Magna inverter. I had (8) 6V Rolls 440aH FLA batteries. They froze solid two years ago and I've been without the solar power since. Let's not get into why they froze, I know why. I'm about to buy new batteries, sadly I cannot afford the 440aH batteries anymore as they've gone way up in price. I was originally considering getting (8) 220aH 6V batteries realizing the reduction of total storage/power. Then, noticing the prices have gone up and it has me re-thinking the 220's.

Can install (8) 120ah 6V batteries for now and then add more batteries for additional storage if not additional power later? Meaning, after a little while longer, could I add 4 more 120 ah batteries for the additional power/storage and still maintain the 48V system?

Thanks in advance for your advice.
Ted

[Sunking]

I have a (low budget) solar pwm controller, which (I read) behaves just a regular charger.

No it does not work like any conventional battery charger. A MPPT Controller acts like a conventional switch mode charger. If you had a DC power supply of 18 to 40 volts would work with a MPPT controller.

I got a sealed lead acid battery that I want to fully charge with the solar controller, before I use it in a live setup.
Could I just attach a regular power supply to the input of the controler, where you normally would attach the solar panel?
I would expect so, but want to double check.

Only if the output of the DC Power Supply is variable between 13.8 to 18 volts. You would have to set the output voltage to 15. to 16 volts. Having said that would be foolish because if you have a variable voltage DC power supply you would not need a battery charger. You would just set the output voltage to 14.4 volts, connect it to the battery, and call it done. When current stops disconnect battery.

The other question is about 18650 Li-ion charging.

I am considering to use a pack of 18650 batteries instead of sealed lead acid. Mostly because of size, but also to
experiment with.
Now, almost all solar controllers are meant for lead acid, so I can't just attach other battery types.
Would it be possible to connect a balancing board/BMS controller (TP4056 for example) to the battery output
or load output of the solar controller?
Not sure if the Solar controller expects to "see" a lead acid battery to the output and get confused somehow.

Forget this idea. 18650 battery does not mean anything, nor is any BMS required. All 18650 means is the size of the battery jar. It does not tell you what kind of lithium battery is inside. It could be NCA, LTO, LMO, NMC, or LFP. Each has it own unique charge voltage from 2.8 to 4.2 volts. Only LFP is compatible with Pb batteries. Unless you fully understand the chemistry and a few years experience with batteries, you are playing with fire and have no biz playing with them. My guess is you have no clue what the alphabet soup is I just went through, which means stay away from 18650 or any lithium Ion battery

[Sunking]

Hi kids,
I am a relatively new guy in the solar world. But, I have installed a 48V system on my off-grid cabin. However there was an issue.

I'll make it short. 48V system, 9 panels, Magna inverter. I had (8) 6V Rolls 440aH FLA batteries. They froze solid two years ago and I've been without the solar power since. Let's not get into why they froze, I know why. I'm about to buy new batteries, sadly I cannot afford the 440aH batteries anymore as they've gone way up in price. I was originally considering getting (8) 220aH 6V batteries realizing the reduction of total storage/power. Then, noticing the prices have gone up and it has me re-thinking the 220's.

Can install (8) 120ah 6V batteries for now and then add more batteries for additional storage if not additional power later? Meaning, after a little while longer, could I add 4 more 120 ah batteries for the additional power/storage and still maintain the 48V system?

Thanks in advance for your advice.
Ted

Quit hijacking threads. Get lost and start your own thread.

[theojkett]

I would start my own thread if I knew how!

[SunEagle]

For security reasons a new member is not allowed to create a new thread until they have been vetted by Solar Pete.