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The input capacitors used in typical inverters are way too small to support the 100 or 120Hz ripple current the inverter generates. They are there to support e.g., the high frequency currents internally generated by high frequency switching within a PWM (pulse-width modulated) sine wave...

Not sine wave, but full-wave rectified sine wave (like you took the absolute value of a sine wave centered around zero). See e.g., https://www.victronenergy.com/live/_media/ve.bus:4._ripple_in_a_ac_battery_system.pdf For a bit more detail, search for "ripple" in...

Clearly this guy, as he says, is not an expert. Quite the opposite, I would say! First of all, any fuse should be able to carry its rated current essentially indefinitely at normal ambient temperatures. The fact that his first 100A fuse test blew the fuse in quite a short time at 100A is a big...

If you read my post, you will see I'm retired. I no longer have ready access to the "behind paywall" research literature and the tools for making extensive searches of that literature. As working professionals, we depend on the paid access provided by our institutions. In any event, that...

Look guys, I'm a physicist with a great deal of power electrical engineering experience, having worked on high voltage AC and DC systems up to the 1000MVA level. I know how to do this and do it safely. Instead of nonsense comments, how about some help with the questions I asked, in particular...

In the light of various recent posts regarding short circuit currents of batteries, and choosing protection devices, etc., and with a general lack of data from manufacturers on Lithium Ion (in particular, LFP) battery short circuit capability, and the wide spread in possible short circuit...

As long as you ordered the Mersen A3T (300VAC) series, you will be fine.

Looking at the Littlefuse data sheet https://www.littelfuse.com/media?resourcetype=datasheets&itemid=68ba338f-8b20-4b97-b7d0-f4fe191d25b2&filename=jlln-jlls-datasheet they list for voltage ratings of JLLN fuses (the 300VAC series): Dc: 160 V (1–60 A) 125 V (70–1200 A) and for interrupting...

I suspect your number of 20kA (which of course needs to be quoted for a particular cell) is well on the high side. I'm not seeing any real data to back this up. Do you have discharge curves for this cell at different rates? That would provide some data.

Could you please quote some actual data in support of that number? BTW, a lot of vendors quote cell impedance at say 1kHz - that is a different animal from the effective series resistance seen with large DC currents. To expand a bit further, Li-Ion batteries have a complicated variation of...

A power of standards (which I don't believe TE-13 has the status of) is to compel people to list safety-critical specification information in order to be compliant. The manufacturers and suppliers "tail" should not be wagging the standards "dog". I take TE-13 to mean that if you have say 4...

TE-13 13.7.8.1 If necessary, a battery bank should be subdivided into units such that the ampere interrupting capacity (AIC) of the overcurrent protection device is not exceeded. NOTE: Generally, fast acting current limiting fuses such as Class T fuses in an approved Class T fuse...

One of the issues here is a lack of data from battery manufacturers (both of individual cells and packaged arrays of cells) regarding the short circuit current capability of Lithium Ion batteries. One thing I am learning is that the short circuit current, expressed in terms of Ah capacity...

Oversized protection can be worse than no protection (in all things) ;-)

That's a common misunderstanding. Lithium Iron Phosphate ARE Lithium Ion Batteries, just one of several common chemistries employed in Lithium Ion Batteries. I think the reason people do this is as an (incorrectly formulated) attempt to distinguish the relatively "safe" LiFePO4 chemistry from...

Just to correct an earlier post about the ABYC standard for Lithium Ion Batteries (TE-13), it does NOT mandate class T fuses. This "Technical Information Report" simply requires fuses of sufficient AIC (Ampere Interrupting Capacity). Unfortunately, as most battery manufacturers I'm aware of...

Class T fuses increase in size (in groups) with increasing current rating. The Blue Sea class T fuse holders (two sizes) only accommodate 110-400A fuses. Below and beyond that (and the fuses go much higher in capacity), you need to provide your own mounting system.