Lishen
Hi David, what were the problems with the Lishen batteries and how does the brand you are currently using differ?
John
Hi John
The problem with the Lishen batteries was not the cells or internal software as we originally believed but simply the connections between the cells breaking down as people bumped their bikes up and down curbs or through pot holes in the road. In some of the batteries the heavy and bulky Lithium Ion cell housings were moving within the case causing stress fractures in the connections between the cells.
During our visit to Lishen in China we discussed the problem at length with a team of about 10 of their top scientists and technicians. I should mention that the Lishen factory and operation is absolutely amazing it was like being in a very hi tech hospital with 3000 staff (2000 of whom are graduates) without any patients! I should also mention that Lishen make cells for Panasonic, Apple (Ipod in particular), Hewlett Packard, Motorola (razor phones) among a list of multinationals as long as your arm. My point is that they know what they are doing.
As an aside I have to mention a very embarrassing moment. After about 10 minutes of discussion in one of the many Lishen meeting rooms, a little lady (I would think about 4'6" and at least 70 to 80 years) came into the meeting room, picked up the tea pot and replenished every ones drinks. Being in a state of high concentration I ignored her and politely nodded my head when she topped me up. After she had finished serving the tea she sat at the head of the table and I am embarrassed to say I smiled and thought "oh no the tea lady sat down, how embarrassing for our hosts" and carried on politely ignoring her. The Lishen team leader then stood up and (you guessed it) said may I introduce Professor Yang, head of Lithium research and the little lady with more than a twinkle in her eye smiled sweetly at us all, and especially me!
Anyway.......
Our new 37v 14a or 518ah is one of the lightest, most powerful and most reliable batteries available (sorry about the plug!
). The big difference is as it is Lithium Ion Polymer rather than the more basic Lithium Ion. In a Lithium Ion Polymer battery every component is solid - there are no liquids that need to be contained by bulky, heavy cell housings as in normal lithium Ion batteries. The result is a powerful, safer, thinner and lighter weight battery with a wide operating temperature range and no memory effect.
Because there are no solid, heavy cell housings the components are all together more flexible and are not prone to cracking or becoming disconnected from each other.
All that said, as soon as Lishen have finished making their alterations, they have intimated that trials will have been finalised by October, we will be revisiting them.
Best regards David