Recent content by toms

Its fine to use as long as you keep it away from surfaces that need to be conductors. ie: use conductive antioxidant between battery and terminal, then coat outside of terminal with dielectric grease to prevent moisture damage.

If the system voltage has been high that should show up in the diagnostic trouble codes of the body module as a history code. That will be separate to the failed component codes.

I imagine one battery 2P4S (two cells in parallel, connected together four in series), the other is just four in series. If that is the case then they are OK to parallel as long as the chemistry is the same (eg both LiFePO4)

Yes, it will work fine as long as they are the same chemistry and series cell count.

Nobody really knows for sure yet, as simulations of <.5C current cycles have to be done in real time. Above that it is literally a different chemical reaction in the cell. The first cells I know that have been constantly gently cycled (3.0 - 3.45V) at maximum 0.5C were commissioned in 2007...

I’m completely off grid in South Australia and have been for over 12 years. I started off with a SMA Sunny Island, which is now CEC approved as a grid tie hybrid. Compatible with SMA Sunnyboy grid tie inverters, and most commonly available batteries. I recently purchased a second hand grid...

I remember seeing a lot of those cells on the market around seven years ago. When I dug a bit deeper they were all coming from cell brokers that were known to deal with factory seconds and refurbished cells. Fully charge that battery, then subject it to the highest load you can and measure...

My LiFePO4 battery is over 12 years old now. It often goes all winter without being fully charged or activating balancing. I wouldn’t worry about it if I were you.

With my LiFePO4 that doesn’t have inverter comms I set my BMS cell LVD to 3.0V, and my inverter LBCO to 50.0V This seems very conservative, but I regularly run that system to inverter shutdown and get over 80% of battery capacity, so I see no reason to stretch the cells any further.

There are zero engineers / chemists that recommend parallel charging LiFePO4 cells to upper knee voltage until current reaches zero. Sadly, too few youtube heros and the sheep that follow them realise that.

Of course it is an accurate method. I’d say over 99% of batteries have their cells balanced by individually charging to a known setpoint.

My advice - ask your cell manufacturer (not reseller), how they balance and match their cells and follow what they say.

That packaging is awesome 🤩

In Australia, private company’s own the power distribution. If you want to participate in their distribution you follow their rules. Our government simply obeys its corporate masters. There is always my preferred option of going off-grid. Unfortunately there is no complete escape as a...

Maybe, but in 2012 when I set up my primary off grid system I chose an SMA Sunny Island. In 2024 I would choose the same inverter.. Some things change - some stay the same.