₦airaland Forum

Tdoctor:
Abeg people,
This is my first lithium build and the cell voltages are doing as they like, even with the so called balancer that came with the BMS.
I want to ask a question for those with experience:
1. Is using a separate active balancer OK, even with the BMS balancer?
2. How many amps active balancer will a 15 KWH battery require?
3. Is there any advantage with a smart active balancer vs. a dumb one?
-
NB: Still balancing out my cells, but I do not know if the 2A supposedly active balancer will be useful if any imbalance occurs again.

dollarnaira:
Try any of these:
1. Dismantle all the cells and charge each cell up to 3.6v.

2. Charge to 58v or so dismantle and reconfigure in parallel for few hours.

3. Charge each to 3.60v from external source after charging to 58v without dismantling. Get a higher amp step down buck converter and connect to any source within the acceptable voltage of buck converter then step down to 3.60v.

Please always request for a top balance from sellers next time.

Your internal and external balancers will work but it will take time.

Tdoctor:
..
I think I followed item 3. No energy to dismantle. These are my readings.
The cells with ink marks are currently being charged with phone USB chargers.
..
Are my cell wire resistances OK?
..
Did anyone shorten their BMS cell wires?
..
Thanks in advance

Tdoctor:
Abeg people,
This is my first lithium build and the cell voltages are doing as they like, even with the so called balancer that came with the BMS.
I want to ask a question for those with experience:
1. Is using a separate active balancer OK, even with the BMS balancer?
2. How many amps active balancer will a 15 KWH battery require?
3. Is there any advantage with a smart active balancer vs. a dumb one?
-
NB: Still balancing out my cells, but I do not know if the 2A supposedly active balancer will be useful if any imbalance occurs again.

dollarnaira:
Try any of these:
1. Dismantle all the cells and charge each cell up to 3.6v.

2. Charge to 58v or so dismantle and reconfigure in parallel for few hours.

3. Charge each to 3.60v from external source after charging to 58v without dismantling. Get a higher amp step down buck converter and connect to any source within the acceptable voltage of buck converter then step down to 3.60v.

Please always request for a top balance from sellers next time.

Your internal and external balancers will work but it will take time.

bassdow:
why gamble when you easily could buy from those in here

micxwell:
Hello bro. I use a LVTOPSUN 5KWH BATTERY, 5KVA GROWATT SPF 5000 ES INVERTER.

I want to ask if this is normal. During the afternoon when the sun is shining, I expect the battery to go completely into idle mode once it gets to 100% but no o; the battery starts discharging by 0.33A.

Regardless of whatever load I put on the inverter, the battery discharge current remains at that 0.30 - 0.33A.

Usually by evening around that 6pm/7pm the battery would have discharged to around 95-96%.

Is this normal, I feel the 100% should just stay (remain idle) there till I start using it around that 6/7pm.

Cc: Valto, dollarnaira, Trippledots, Dam5reey.

bassdow:
I have experienced such before but it's been very very long. First check your charge controller (if not using Hybrid inverter) else check to ensure the Charging system is not cutting off due to capacity.
To best of my knowledge, such only happens when the Sun comes out very very well (when the charger's output is high enough).

Hopefully, the charging system is configurable

lungwun:
What's a tested and trusted 1.5hp inverter AC that cools well and is a true inverter model (not just inverter on the branding) and is perfect for 3.6kw hybrid inverters?

Make and model will be perfect so I can go source the exact one.

micxwell:
The inverter charges the battery directly. i don't use a Charge controller.

bassdow:
most times, when the output coming from the Solar panels is higher than necessary, it stops recharging the battery till the solar panels output drops. Hence reason it could work perfectly fine before 12pm but the moment enough sunLight comes out, the issue would start. You might need a higer capacity or modify the settings of your charge Controller / Hybrid inverter

micxwell:
I don't have a problem with recharging. After the battery becomes full; I expect it to remain at that "100%", on the display of LVTOPSUN batteries you'll see IDLE when the inverter is not pulling any power from the battery.

But my battery trickle discharges with "0.3 to 0.33A" down from 100%. It stays there like that and by 6/7pm it'll be at 96%. Even if you load the inverter with a pumping machine and a pressing iron at the same time; the current draw from the battery stays at that '0.3-0.33A"; all other power draw comes from the panels.

The inverter will only charge the battery back to 100% only when it drops below 90%

micxwell:
I don't have a problem with recharging. After the battery becomes full; I expect it to remain at that "100%", on the display of LVTOPSUN batteries you'll see IDLE when the inverter is not pulling any power from the battery.

But my battery trickle discharges with "0.3 to 0.33A" down from 100%. It stays there like that and by 6/7pm it'll be at 96%. Even if you load the inverter with a pumping machine and a pressing iron at the same time; the current draw from the battery stays at that '0.3-0.33A"; all other power draw comes from the panels.

The inverter will only charge the battery back to 100% only when it drops below 90%

micxwell:
I don't have a problem with recharging. After the battery becomes full; I expect it to remain at that "100%", on the display of LVTOPSUN batteries you'll see IDLE when the inverter is not pulling any power from the battery.

But my battery trickle discharges with "0.3 to 0.33A" down from 100%. It stays there like that and by 6/7pm it'll be at 96%. Even if you load the inverter with a pumping machine and a pressing iron at the same time; the current draw from the battery stays at that '0.3-0.33A"; all other power draw comes from the panels.

The inverter will only charge the battery back to 100% only when it drops below 90%

bassdow:
Ah
Now I get you; issue ain't what I thought earlier. It's more like when it gets to float stage, it disconnects. Well I presume this should be a configuration issue. Since it gets to 100% and stops charging; rather than continue floating. See eh, I don't know that your model BUT this should be a configuration issue.
mayBe you go through the settings or share your settings screen with us. The floating voltage is either not set or wrongly set or probably it disconnects . You might have to share your settings screen with us. Hopefully others could share their own inputs. Me dey come dey go

AndroBlaze:
What is more helpful is what the voltage is saying and not the percentages.

What voltage does it get to when it's 100% and what voltage does it settle at when it gets to 97% or continues to decline.

Also check the voltage you set as float, this might be key...I don't really see a problem yet, besides something not being configured properly.

What should concern you is ruling out a battery problem which can be achieved by monitoring the voltage behaviour all the way down to the individual cells.

finebois:
is there communication between your inverter and battery

micxwell:
Yes, very much active. At first I assumed maybe that's the way Growatts inverters are designed to work; but I've seen a few online that stays idle without any power draw during the afternoon.

munchies:
Please I want to ask. Is it safe practice to use 2.5mm cable for 2 620w panels on a solar generator??

HeavenlyBang:
Can't recommend below 4mm for that. Cable quality in Nigeria is already pretty bad.

Fakeisfake:
Heavenly, you can say that again. Cable quality in NIGERIA is out of control.

I went to buy another 16mm to make some small upgrade, just as a premonition, I took a short lent of my current 10mm along. The total strands of the 16mm I was offered was not even up to the strands of the 10mm I was holding but the isolation/wrap of this supposed 16mm was making it all looking like a 25mm cable. Went round and it was all same mess. Had to improvise by using the two core as 1core for each +- lines...

How did we get here in just everything...

dollarnaira:
Try any of these:
1. Dismantle all the cells and charge each cell up to 3.6v.

2. Charge to 58v or so dismantle and reconfigure in parallel for few hours.

3. Charge each to 3.60v from external source after charging to 58v without dismantling. Get a higher amp step down buck converter and connect to any source within the acceptable voltage of buck converter then step down to 3.60v.

Please always request for a top balance from sellers next time.

Your internal and external balancers will work but it will take time.

Fakeisfake:
Heavenly, you can say that again. Cable quality in NIGERIA is out of control.

I went to buy another 16mm to make some small upgrade, just as a premonition, I took a short lent of my current 10mm along. The total strands of the 16mm I was offered was not even up to the strands of the 10mm I was holding but the isolation/wrap of this supposed 16mm was making it all looking like a 25mm cable. Went round and it was all same mess. Had to improvise by using the two core as 1core for each +- lines...

How did we get here in just everything...

bassdow:
I have experienced such before but it's been very very long. First check your charge controller (if not using Hybrid inverter) else check to ensure the Charging system is not cutting off due to capacity.
To best of my knowledge, such only happens when the Sun comes out very very well (when the charger's output is high enough).

Hopefully, the charging system is configurable

micxwell:
Hello bro. I use a LVTOPSUN 5KWH BATTERY, 5KVA GROWATT SPF 5000 ES INVERTER.

I want to ask if this is normal. During the afternoon when the sun is shining, I expect the battery to go completely into idle mode once it gets to 100% but no o; the battery starts discharging by 0.33A.

Regardless of whatever load I put on the inverter, the battery discharge current remains at that 0.30 - 0.33A.

Usually by evening around that 6pm/7pm the battery would have discharged to around 95-96%.

Is this normal, I feel the 100% should just stay (remain idle) there till I start using it around that 6/7pm.

Cc: Valto, dollarnaira, Trippledots, Dam5reey.

Tdoctor:
..
I have humbled myself and dismantled the setup to do top balancing

Dam5reey:
It's normal na.
Your charging stop at 100% and resumes at 95%.
So nothing to worry about.

Tdoctor:
..
I have humbled myself and dismantled the setup to do top balancing

Dam5reey:
For DIY to be perfect you need some Special tools and time testing before putting them into box.

Loosed connections can contribute to Cell voltage imbalance.

I built my first batteries used and still working till date.

In 2025, where batteries as their lowest price, You shouldn't be doing DIY, it's expensive task risk is too high, someone had his cells Swollen and had to replace the whole batteries.

It's not even cost effective to do in the first place.

If you want to learn and have fun, perfect it buy building 4s, then 8s, then 16s

Fakeisfake:
Heavenly, you can say that again. Cable quality in NIGERIA is out of control.

I went to buy another 16mm to make some small upgrade, just as a premonition, I took a short lent of my current 10mm along. The total strands of the 16mm I was offered was not even up to the strands of the 10mm I was holding but the isolation/wrap of this supposed 16mm was making it all looking like a 25mm cable. Went round and it was all same mess. Had to improvise by using the two core as 1core for each +- lines...

How did we get here in just everything...