Lifepo4 voltage drop recently
- Thread starter Echo Dawn
- Start date
RV8R
Solar Enthusiast
And if you notice in any of the photos I’ve seen of people enjoying their machines and toys there’s no pictures of their batteries or products in their use…
Ya;
They need to “up their game”. I notice the single paper manual doesn’t even have their company name on it.
Without much involvement, I am just going to assume big on internet sales & low on customer support.
I try to buy chargers that are “User Programmable” ( also multi battery chemistry ). You might want to consider that for any future charger.
Victron 100 | 50 MPPT - User Programable
Kisae 1250 DC2DC & Solar - User Programable “ & Kisae “Surrey BC” the bestbtech support I have ever experienced
,,, phenomenal
MisterSandals
Participation Medalist
Battery voltage measurement is only meaningful for a battery at rest. You posted pics of your 60A charger showing 14.4V while charging and your Rover SCC showing 13.5V while charging.
If charged quickly up to a certain voltage and not allowed to absorb, this is mostly just a surface charge. Imaging splashing water on a sponge to where it feels very wet while the inside may be very dry. Given enough time to settle, the surface charge will be absorbed more evenly throughout and a measurement on the surface will be more representative of the overall saturation. (sorry for mixing terms metaphorically.
Similarly, when your charger reads 14.4V and you think the battery is fully charged to that level, applying even a modest load will quickly burn off this surface charge and the voltage will drop drastically.
If you were to hold the battery at 14.4V until the charge current drops to well under an amp, then your battery would become fully charged. This has been mentioned several times in different ways but i have not seen that you have achieved this.
Yes, that is all probably very accurate. Except the rover was showing the voltage from the battery I guess, it wasn’t charging “as well”
I am a total newbie here with lithium.
I am learning so much very quickly, and I really appreciate your words because I think I just learned a whole lot more there too
Thank you
I will attach a screenshot if I have one of the moments leading up to me turning off the charger I know it was very low input when I shut it down but less than one amp I cannot say that.
I am a total newbie here with lithium.
I am learning so much very quickly, and I really appreciate your words because I think I just learned a whole lot more there too
Thank you
I will attach a screenshot if I have one of the moments leading up to me turning off the charger I know it was very low input when I shut it down but less than one amp I cannot say that.
MisterSandals
Participation Medalist
Charging at 2.6A is far from being at rest. What was the top charging current and was it tapering down to this 2.6A?
Yes, the top charge was 60+ amps and then it gradually went down my chargers green light went on. I kept letting it go and go and go. It was 1:30 in the morning, and I was bagged and decided to shut it down not knowing how detrimental that little extra bit would be until now.
MisterSandals
Participation Medalist
I wouldn't call it detrimental. If it tapered down to 2.6A over a period of several hours it probably got a decent charge.
Consider this voltage vs SoC chart.
The 2nd chart, 12V Battery Pack, charged to 14.6V is 100%. A very modest load, taking it down to 99% is at 13.5V. This is largely the surface charge being burned off.
From there, the discharge is VERY flat and this is where judging SoC based on voltage becomes more difficult. The first 1% SoC resulted in a 1.1V drop. The next 70% discharge results in roughly .5V drop.
Still, while being charged, battery voltage measurement is pretty meaningless. From this point, stop the charger for 15 minutes and check the voltage. Then apply a modest 100W load for a few minutes. Remove load and measure.
sunshine_eggo
Happy Breffast!
It'd mind boggling that there's four new pages since I last logged on.
I don't have the time to parse all this, so I'll finish with this:
Stop doing things without asking first. Things like hitting the reset button may force the BMS to re-guess SoC based purely on voltage which completely defeats the purpose. 52% @ ~3.302V cell voltage under load is not particularly accurate, but based on these values, it's consistent with a guess, i.e., 3.302V is between 50 and 60%, but closer to 50%:
Your rapid fire posts and emotional swings make helping you almost impossible.
The ONLY problem I see here is user error/bad practices. There may be other issues, but until you slow down, listen and stop doing things randomly, you're not going to get help.
I don't have the time to parse all this, so I'll finish with this:
Stop doing things without asking first. Things like hitting the reset button may force the BMS to re-guess SoC based purely on voltage which completely defeats the purpose. 52% @ ~3.302V cell voltage under load is not particularly accurate, but based on these values, it's consistent with a guess, i.e., 3.302V is between 50 and 60%, but closer to 50%:
Your rapid fire posts and emotional swings make helping you almost impossible.
The ONLY problem I see here is user error/bad practices. There may be other issues, but until you slow down, listen and stop doing things randomly, you're not going to get help.
ScrotpusGobbleBottom
Corn Pop was a bad dude.
It isn't alarming.
Soc, voltage, and draw makes sense with your battery.
ScrotpusGobbleBottom
Corn Pop was a bad dude.
The chart that you have been given is the math. We only have that plus experience.
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