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But take care: Aluminium could be very annoying due to the strong surface oxidation.

One :-) But this number also depends on desired target RdsOn/max acceptable heat dissipation.

You can use the same cables or attach separate wires in parallel, whatever you prefer.

Depending on size, jlcpcb.com could be affordable, too.

"CE" is NOT a certification but a declaration from the vendor that a products fulfills certain specification(s). Thus, the provided documents could be just okay. If you want to enforce that certain (EN-) specifications are fulfilled, it might be necessary to inspect the detailled test reports...

A step-down converter will easily whitstand millions of power-cycles - or at least much more cycles than a high power relay will whitstand.

If I were you, I would discard all batteries below 2.5V - for safety reasons. And yes, those batteries are crap.

I guess you're comparing RMB/Wh vs RMB/Ah ....

As a general rule (at least when using battieries with integrated BMS), only identical can/should be put in series or parallel. Depending on used BMS, there could be some limitations (i.e. only putting in series permitted). 100..200W is easily achieveable with some generic 24/12V step-down...

+1 on trying to keep the system as simple as possible ? Using 24V makes only sense when using 24V inverters, too. So, starting with 12V and then moving to 24V requires new inverters. What are your power needs for 12V-only systems? 10..100...1000W? Maybe a simple 24/12V stepdown converter would...

Imho there is no "cheap"ready-for-use solution available. My personal approach would be: - avoid any (expensive) switching on high current 12V side - Buy an (inexpensive) inverter with remote control which fits the power needs - Build the desired logic (i.e. temp sensors...) with some...

Maybe a silly idea: what about using other kind of temp sensor with more noise immunity, like DS18B2x or NTC or....?

Sure, but in diy appliances, busbars are normally used way below it's rated limit. So much less heat. If the thread creator would tell busbar size and amps, we could do the math...

Imho busbars shouldn't get "hot" as lang as they aren't undersized.

Ouch, looks I was wrong.... - seems to be LiFePo, not Li(Co)Po

I'm pretty sure that all commercially available MPPT controllers are using kind of PWM, don't they? All other potential possibilities I'm aware of are either expensive, inefficient or both.... Thus, the already mentioned conclusion is MPPT is PWM with "smart dynamic adjustment"...?

You need a 16s LiPo, not a LFP BMS - or a BMS with adjustable voltage settings! Edit: my claim was wrong, just read the screenshots above...

Panel order doesn't matter - the resulting wattage will be identical.

Sounds like a defective BMS....

Well... It depends if several low voltage cutoff/on cycles are an issue for your given use-case or not. From battery health perspectives, some on/off cycles aren't a big issue as long as the low voltage cutoff level is properly choosen. Btw, I'm unsure how other BMS models/brands react to low...

On some smart BMS, the recovery voltage can be adjusted. In case of a thumb BMS, recovery voltage is fixed. In case of large currents, OC battery voltage might trip recovery voltage level, so there is imho no solution...

Sorry for the dumb OT question: Why?

It's questionable if (mechanical) relays are fast enough to prevent a BMS from overvoltage events. I'd still vote for some kind of crowbar - i.e. with a thyristor and a simple zener diode. Of course, this crowbar must then trigger some kind of interruptor (circuit breaker/blowing fuse...

Exactly: To get proper W(h) or Voltage readings on capacity tester on higher currents, a four wire version is required. And current readings could be off due to poor calibration and/or measurement errors/tolerances: With an effective current of 10A, a BMS with a measurement range of 200A and 1%...

The JBD/Overkill BMS also support amp reading calibration (as seen on the Daly which imho use similar BMS IC), don't they? If yes, just perform a calibration. You might need a third Jesus/Ampmeter to proof the readings...

Voltage drop would explain a difference in voltage readings (and Wh readings) - not in Amps. My guess: The amp offset is due to read errors caused by the BMS. The BMS has a much wider Amps reading range whereas the shown capacity tester's max current is a fraction of the BMS's one. Thus, large...

To know the size of the required capacitor, you need the following information: -Inrush current -Inrush duration -Acceptable voltage drop The first two values can be grabbed by measuring with an oscilloscope. The latter depends on battery health/SOC, cabling and inverter low voltage...

Assuming a proper design (wire thickness, wire length, battery health/IR), a capacitor requires a LOT of Farads to have any noticeable effect on large (inrush) currents. My advise: don't spend money for expensive huge caps.

Never heard about that. As long as the heating element is isolated from Water and only resistive, there is absolutely no performance difference between AC and DC. But as said, DC could be an issue for electromechanical thermostats.

As long as the battery is effectively placed in a way where fire isn't an issue in any case (even while being away), I wouldn't hesitate to buy it. Just check if you could imagine being safe when (in theory) placing a _huge_ fire on desired battery location and then walking away for 12 hours or...

Sure, they will. Here an example from ANZ bank dispute form I found:

"Item not as described" is a standard use-case in credit card chargeback handling. You will get the money back if you can proof (substantial) differences. But: depending on "terms and conditions" of the shop, you might be required to send back the stuff for refund/chargeback. Due to obvious...

Maybe sodium acetate would fit....?

I can't check if they are really genuine, but tested all cell's capacity with a Li500 charger. I only used Low-C batteries like NCR18650, thus I never checked internal resistance. But for high-C cells/rates, I'd recommend to also validate internal resistance against specification i.e. by using...

In theory, a standard bus bar can handle much, much more than 48V. But when exceeding ~50V, touch prevention mechanisms have to be part of the game to gain approvals.