Recent content by MondeoMan

Tested yesterday and today. The problem follows the cell (moves with the cell). I could not see any issue with the terminals (1-2 mV drop between busbar and physical cell terminal base at 60 Amps).

Hi All, I just bought 32 cells, rated 230Ah with the exact same square terminal as shown in the picture from the start of this thread. I bought them from a local reseller (I'm from an Eastern European country). I have reasons to suspect that the reseller buys them in bulk quantities from Docan...

What type of Analog Front-End does the JK use? A dedicated AFE BMS chip? Analog multiplexers to MCU ADC inputs? But what about Level Translation in this case? Differential amplifiers with high common-mode rejection?

Sorry I do not understand. I do not really know ... what? I know the charging current and the duration that this current was maintained. I also have a second confirmation of the accumulated charge (AH) via the Coulomb Counter. You take a 200 Ah cell, resting at 2.75V, and you charge it 4A for 2...

The accumulated AH reading was confirmed by the Coulomb Counter (Victron BMV-712). I am sure it took 40 Amps at the end of the 5 hours, it was still in Bulk charging and I was checking on it every hour. Absorption was set to the mythical 3.65 * 8 = 29.2V, but I did not let it get there...

Let me put it another way... I started with a new 200 Ah cell that I have drained until the resting voltage was stable at 2.75 volts for about two days. Then I started charging with a constant 4 A for 2 hrs and then constant 40 A. After 5 more hours, the cell voltage was 3.48 V, if I remember...

No, sir. All cells, new and old, show this effect: a temporary rise in cell voltage during charging, that slowly drains off after disconnecting the charger, and then the terminal voltage of the battery drops to the resting voltage. The rise in voltage is in direct relation to the charge...

Just as a side-note, if you look at the datasheet, they give 14.6 V as "fully charged voltage", but also a 20 A charge current for a 40 Ah battery. That's a 0.5 C rate, which causes a significant rise in cell voltage during charge, due to "Ohm's law", as BiduleOhm called it. In reality, it's...

10 A is a slow charge current for 80 Ah. They're probably already full at 13.6V...the additional charge up to 14.62V is going to be overcharge. Are you able to monitor individual cell voltages? Do they really need re-balancing at each charge cycle? How big is the imbalance at around 14V?

What's the AH rating of the Valence RT batteries?

From my experience, watching the voltage rise while charging, I would say below 0.2 C Sorry, I don't understand the question. Many detect charge termination and "synchronize" to 100% SOC when cell voltage exceeds a set value on all cells. I assume that capacity reading is the SOC (State Of...

One more thing I want to clarify. Coulomb counting starting from a known reference is good only for a limited number of cycles, let's say 5 cycles. After more cycles than that, errors begin to accumulate and the readings will be wildly inaccurate. But it still is the best method to get an idea...

I'm sorry to disappoint you, but there is no standard answer. It all depends on your typical charge currents, battery capacity, personal preferences. Best I can tell you is to watch your coulomb counter and adjust your setup based on what you measure. I cannot give you a voltage guideline...

So just to clarify. I had a BMS 8T. the Power Supply slide switch was in the EXTERNAL position I unplugged the jack providing external power When I saw 5.50 mA current consumption on (8+), I started disconnecting other plugs to see if if makes any difference. I clearly remember that when I...

You need a BMS to clean up the mess that the BMS creates...not my cup of tea. Maybe we are exaggerating with this need to balance, balance, balance, day after day, and the cells would stay in balance by themselves if left alone and not abused. Then the BMS is just another weak link, something...