[centizen]

They are even matching the internal resistance of the cells, I can't think of much more a professional manufacturer would be doing. As long as they are getting their cells from reputable sources (big if) I don't see anything wrong with a boutique battery industry for niche applications.

[wolverine876]

> I can't think of much more a professional manufacturer would be doing

Safety equipment, in a safe environment, not exposing others to fire risk?

[morphle]

A professional manufacturer would not put any cell in series but instead would have a charger/discharger with voltage per cell, with current and temperature sensors as feedback loops. The danger of cells in series differs with the cell chemistries.

Using a BMS is another indication they are not professional or even had an engineer design them.

Sadly I know of only a very few small professional battery pack manufacturers, certainly none of the EV or bike makers.

[_fizz_buzz_]

> A professional manufacturer would not put any cell in series but instead would have a charger/discharger with voltage per cell

My Bosch e-bike has 4 cells in parallel and put 10 of those in series. This so called 10S4P is a very typical setup for e-bikes. Each individual cell does definitely not have their own current/temp sensor. The BMS will check voltage for each of the 4 cell blocks.

[sbierwagen]

By "series" do you mean "parallel"?

Note that Tesla famously used a 6-series/74-parallel configuration in the Model S's battery pack: https://circuitdigest.com/article/tesla-model-s-battery-syst...

Each pack only had a single BMS connection for every clump of 74 cells! Presumably they only got away with doing this by doing extensive binning/characterization of the cells before building them into packs.

[ClumsyPilot]

> Using a BMS is another indication they are not professional or even had an engineer design them.

What is the proper alternative? Do any ebike packs conform to the standard you expect?