Battery Journal →

The BMS says 100A. The whole battery says what?

One big number on a BMS, suddenly the whole setup damn power. Wait. We haven’t even asked about the cells yet.

Open EM5 battery assembly with a protection board, blue wires and insulation.

An invented conversation. The 100A label is an illustration, not a specification for any pictured battery.

“bro this one 100A”

“which part ah?”

“the battery lah. see the BMS”

eh, u changed subject halfway through your own sentence sia

first u said battery. then u showed one board

that board matters lah, but it didn’t magically upgrade everything connected to it

knn, setup keeps cutting out then don’t bypass protection or keep raising settings. Stop using it and get the cause assessed. Now let’s see why that one number isn’t enough

Follow where the current goes

Eh hello, start with the actual cells and how the pack is configured. Then check the connections, busbars, wiring, connectors and protection; the enclosure and heat matter too.

The whole path has to be considered. Bigger number on one part doesn’t establish the rating of the whole assembly.

Walao, imagine changing the biggest number on the shopping list and telling the rest of the parts, “ok u all tahan ah”.

They never agreed lah.

Protection doesn’t mean can do anything

Steady, a BMS can monitor things like voltage, current and temperature and provide protection, depending on its design and settings. It doesn’t make the cells or wires stronger.

Then ask what the number means. Continuous rating and brief peak aren’t interchangeable. Peak for how long, under what conditions, and is this from the board listing or the complete pack’s documented specification?

Numbers help only when we know which part, conditions and duration they describe.

If all we got is “100A bro”, then all we got is a claim with a unit behind it lor.

Texas Instruments BQ76952 battery monitor and protector ↗

Show us the setup

Okay bro, send the battery specification, controller label and charger label first. Got a pack build record, include it. Don’t remove the casing for a photo.

We need to see how the parts relate, not whichever screenshot has the biggest number.

Sometimes answer is “not enough information yet”. Better than anyhow give u a number lah.

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