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Comment by jpgvm | Hacker News Reader

> better quality than what I assume is the alternative, imported Chinese batteries.

You do realise that China makes some of the worlds best batteries right?

There is a reason why BYD, EVE and CATL are in the news all the time and it's not because they suck.

Quality wise Chinese/Korean/Japanese batteries are all pretty much the same on NCA/NCM chemistries. China has a big advantage in LFP but LFP is shitty for an e-bike because the reduced density penalty is much more meaningful than in a car.

Those companies make cells of course but there is also plenty of high quality BMS available and fully assembled batteries out of China too obviously.

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China also makes some of the worlds worst batteries. (Source: all the products I had to return after 1 or fewer successful charges.)

They are doing exactly what the advocates of free market dream of. You want to pay as little as possible, you get the crappiest stuff, you are willing to pay more to get top quality, you get good stuff.

That would be fine if there was a way to differentiate crap from not crap. Price is a signal, but an increasingly shitty one in that I can pay a high price and still receive crap.

The free market is happy to sell me crap at high prices with no ability to know that until the deal is irreversible.

The theoretical free market also has perfect information, and the current markets actively work to obscure that.

In many product categories there is no top stuff, just keep buying the crap stuff until you find the specimen that works. Maybe "keep repeating" is a proxy for free market goodness, I can honestly not tell anymore. :-D

They are having huge issues with e-bike fires in China. Here you have an article with two Chinese researchers weighing in on the issue.[0] According to them low quality batteries are the reason for the number of deadly fires.

So yes, Chinese ebike batteries are on a whole of low quality.

[0] https://www.sixthtone.com/news/1013638

Given the numbers cited there it looks like Chinese e-bikes have a fire rate of 0.002391% per year. From a quick search it seems like there were about 130 e-bike fires in NYC in 2022 out of a population of about 65000 e-bikes, so NYC based e-bikes have a failure rate of 0.2% per year which seems significantly worse than the cheap ones used throughout China.

I don't think there has been any sort of reliable survey on the quantity of ebikes in NYC, and 65,000 is likely to be extremely low. There is no registration or point-of-sale reporting requirement.

There are also large quantities of unregistered electric and gasoline mopeds and motorcycles, many of which are also labeled as ebikes by either their manufacturers/importers or public authorities when involved in an incident.

One can purchase custom-made ebike batteries in NYC from shops similar to the one in this article, often with substantially worse finishing/packaging quality and unknown BMS quality. And said batteries are often run hard in delivery service in 4-season conditions, including exposure to temperatures well below freezing and salty slush spray, then charged via chargers and cords of unknown quality plugged into what are often pre-WWII electrical systems.

The FDNY is appropriately raiding custom battery shops in NYC, since there doesn't seem to be an appropriate regulatory system yet for custom-manufacturing this sort of energy storage device in a dense urban environment yet: https://ny1.com/nyc/all-boroughs/news/2024/02/09/queens-biz-...

Did you read what the experts said? It doesn't matter if the incident rate is higher in NYC, anything about NYC has no bearing on this. The fires in china are due to low quality batteries.

Do you really think these bicycle batteries are being powered by BYD? Like I said I don't know the their market well but if its similar to other markets in the region, they are importing low quality generic branded stuff that may be worse off than those local manufacturer who have a real incentive to try to product higher quality products.

The quality of individual cells does not necessarily have any bearing on the safety of the finished battery/BMS/charger.

Never suggested otherwise.

Do you really think there are tons of dodgy Chinese companies producing battery cells? A notoriously technically difficult, capital intensive and above all massively competitive business with tiny margins unless you are running the absolute best process at enormous scale?

No. There is just a handful of companies producing cells at reasonable scale and cost. Pretty much every cell you can buy from Alibaba (which is almost certainly where these e-bike pack makers are buying from) come from just 7 companies: CATL, BYD, EVE, CALB, Gotion, Sunwoda and Farasis.

All of these companies make high quality cells and these are definitely the only ones with a good enough price/performance to shove in a hand-made e-bike pack and make a profit.

This notion that Chinese batteries are somehow bad is ludicrous and the lengths people go to state as fact something they clearly have no experience with is intellectual dishonesty at best.

The fact is that there are demonstrably under-specced batteries being sold. (https://www.youtube.com/watch?v=qMZuHMlRw_0&t=579s)

Is this just a case of people buying reputable batteries and selling them under their own brand name with higher specs? If so, why do these 7 manufacturers make bad batteries?

Clearly there are plenty of badly made cells out there, so I think I'm misunderstanding something.

> Do you really think there are tons of dodgy Chinese companies producing battery cells?

Are you serious? Yes, obviously. Spend 5 minutes on Alibaba looking at the panoply of companies selling cheap cells, and reading forum posts from people who build their own batteries unfortunate enough to buy those cells.

I can see you are very passionate on this topic. I did not realize in the article that these shops were actually making individual cells but the rather the complete pack. My notion was that the complete pack may be safer than complete packs coming from china under generic fake names. Thanks for clearing it up. You clearly have a lot of experience in this area with incredible honesty but low capability at following thoughts.

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