Ebikes

E-Bike batteries from China – Visit at Tianneng company

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With our group of around 20 international e-bike experts we arrived this morning from the Hotel in Changxing at the headquarters of Tianneng Battery company – welcomed by the CEO and several high level representatives of the company we first we saw a battery museum that covers a brief history of batteries and their production starting in 1600 in Europe. The companies history was of course also in the focus.

Tianneng and the Chinese market

Founded in 1986 the brand sees a huge growing ever since – today 20.000 people are working in around 25 production sites around China. The company covers 40% of the Chinese market for e-bike batteries. Mainly lead acid batteries (export is not very relevant until now).

Lead acid is of course a threat to the environment, and one main topic of our trip is to discuss with Chinese companies and policy makers from the Chinese Bicyle Association (CBA) how to quickly increase the share of Li-Ion batteries in the market.

At least though, there seems to be a quite well working lead acid recycling system: By law a producer has to take used batteries back and consumers get a refund when they return the battery tot the retailer (around 1/3 of the price). This very high refund value causes a high recycling rate – over 90% as Chinese experts estimate. Tianneng in the last years has started to produce Li-Ion cylindrical cells used in e-bikes, see pictures below. The recycling is in planning and going to start soon.

e-bike Batteries require high quality cells

I learned from our groups experts Hannes Neupert (ExtraEnergy) and Rüdiger Niereschner (Energy Tube) that in Li-Ion battery production, precision and perfect cleanliness are the key to quality. As Humans make mistakes an ideal battery production factory is highly automatized. As you can see on the pictures the production of Li-Ion batteries at Tianneng is still involving a lot of workers and according to the experts in our group, the hygiene is not absolute top level. This may result in quality issues and higher rates of defect cells.

Now why is that a problem especially for e-bikes?

A short answer: Big batteries consist in a lot of cells and, very briefly said, the quality of a battery depends upon the quality of its weakest cell. So the more cells you put into one battery, the higher the risk of a failing one. An e-bike pack usually has 40 cells or more, thus the risk of a bad one is much higher than when you look at a battery pack used to charge a smartphone that has maybe two cells.

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Global competition: High quality and good reputation required

Tianneng would like to export Li-Ion round cells to global e-bike markets as their chairman underlined in a chat we had after the tour – the global market is dominated rather by Japanese and Korean products – not only have they got very high quality standards but also a good reputation. And this reputation is the second key to export chances – easy to explain why: When you buy some thousands or millions of cells from, it will take 3 or 4 years until you know if they were good – or if you know earlier, they must have been bad :-).

As Chinese battery producers in general are seen with skepticism, even if their quality was perfect now, it will be hard years for them to get into international markets. However with their strong background in a growing domestic market where 35 Millions of e-bikes are sold yearly at the moment, Tianneng and other Chinese battery brands might as well have that patience.

The e-Bike Tour in China and Taiwan

More e-Rad Hafen