How easy/hard is it to fix a Lithium Ion battery?

[The Maestro]

I've had two batteries, one plus a replacement for my Alien 36 Volt kit and they have both broken in the same way. One of them now only puts out 21 Volts (this is the fairly new replacement that I've had about a month) and the other older one now only outputs 12 Volts!! I think its connections that have come loose inside the battery. I'm pretty sure that one of them died when I went over a slight bump which maybe loosened some wiring inside.

I've actually fixed both of the batteries once where the wiring to the back of the on/off key had come loose and I soldered it back on but I think these new problems are deeper inside the battery. I'm not even sure that I can get the battery out of the metal casing, let alone fix it. Is this something that is even worth trying?

Sending them back isn't an option as I've obviously opened both of them up already and voided the warrenty. Alien were actually really good about helping and sent a replacement without even asking me to send the original one back but I had so many problems with yje batteries (had numerous other problems I haven't gone into which I also managed to fix) that I eventually got impatient and opened them up mainly because I rely on the bike as my main form of transport. I suppose I could ask them to send another one out but I don't really like asking for my 3rd battery

 

[drgcb]

I've just had exactly the same issue with my Alien 36V battery. Initially the battery kept cutting out when going over bumps, but could be 'rebooted' by turning the ignition key to off and then back on again. Back to Alien for a new ignition. Then when the battery was returned it wouldn't work at all, and testing the output I was only getting 23V. A replacement was requested and sent without hesitation, so good service from Alien once again.

Let's hope this one lasts now. I also rely on the bike for commuting and have been unable to ride for a couple of weeks because of the problems. Plus all my new-found muscles appear to have disappeared

So there's clearly some quality control issue / design flaw going on there. I'd still talk to Alien, because it's obviously not an isolated incident and they need to know to take things up with their supplier.

 

[flecc]

If it's just internal wiring connections it may be possible, but it's much more likely to be the internal battery management circuitry which is very complex on lithium batteries. There's individual monitoring circuits for charge control of cells and a master circuit controlling those and the current issuing under load.

If you have a look at the page below on my Torq website you'll see the internals of it's Phylion Lithium battery that I've stripped and photographed by way of illustration:

eZee Li-ion battery
.

 

[The Maestro]

I've just had exactly the same issue with my Alien 36V battery. Initially the battery kept cutting out when going over bumps, but could be 'rebooted' by turning the ignition key to off and then back on again. Back to Alien for a new ignition. Then when the battery was returned it wouldn't work at all, and testing the output I was only getting 23V. A replacement was requested and sent without hesitation, so good service from Alien once again.

I think its likely that these batteries have several common problems because I had the intermittent problem you describe too. I think its a bad connection in the key barrel because sometimes I found just jiggling the key around made it come back to life but other times I'd have to 'reboot' it like you say. That was the original issue I got a replacement for (before it broke completely). The replacement was also DOA but this time it was just a duff fuse.

Its a pity the battery seems a weak link in this kit, Alien customer service and the rest of the kit is very good.

 

[The Maestro]

If it's just internal wiring connections it may be possible, but it's much more likely to be the internal battery management circuitry which is very complex on lithium batteries. There's individual monitoring circuits for charge control of cells and a master circuit controlling those and the current issuing under load.

If you have a look at the page below on my Torq website you'll see the internals of it's Phylion Lithium battery that I've stripped and photographed by way of illustration:

eZee Li-ion battery
.

Thanks for that info Flecc, it seems like its probably a bit more complicated than I expected. I sort of imagined that the battery cells inside were split into groups and wired in parallel and then finally wired in series. I though my problem might have been that one of the groups of cells had got disconnected from the circuit resulting in the reduced voltage. Probably a battery management problem like you say though

One other thing, are all batteries this bad? I was thinking of getting a Ping or similar but if I had a problem, sending it back to china wouldn't really be an option.

 

[flecc]

Most have been getting a lot better, but there has been the odd incidence of trouble still occurring such as this Alien batch. Those who've bought the Ping battery have been lucky so far, but lithium iron is a very new technology which the bike manufacturers have found not reliable enough yet to adopt.

That said, much depends on the quality of manufacture and assembly, and Ping seems to be a very dependable person to date in this respect and seems dedicated to his product.
.

 

[The Maestro]

Just thought I'd say that I've just got the internals out of one of the batteries and one thing I noticed was that there was a lot of water ingress and quite a lot of the inside was caked with rusty sludge water, many of the contacts were rusty.

It might be an idea if owners of this model consider some waterproofing measures such as putting a cover over the battery especially if riding regularly in wet weather.

 

[bogmonster]

I looked about a fair bit on the forums before ordering a battery. Ping's seem to be reliable unless you go for the high power stuff like some in NA do. We are talking 72v 40a configs. People have reported BMS failures then. The Ping's have been about for a year and appear to be lasting well. Ping started using new cells that he called v2. These have not been around as long but still no real issues reported. The V1 calls are availiable again as well and that is what I have ordered.

I have not heard of any real issues on the Wister 14ah battery either. I was tempted to get one of these and the Wisper folk were happy to sell me one despite the fact that I didn't have a Wisper. The current version of the battery has a connector similar to a kettle lead and should be easy to convert and use. I beleive the new verison will have contacts on the base so maybe not so easy to use on another bike?

Whatever you use, a waterproof (and puncture proof) case is vital in my opinion. Farnells have a good range if IP rated enclosures.

I have not got my Ping battery yet so can't comment on how good it is and of course only time will tell. He has been very helpfull and appears very knowledgable. Now, if customs could get a move on and release the battery....

It is a shame the Alien do not sell the motor alone or built into a wheel. Currently you can only get the motor in a complete kit. I have asked if it is possible to get just the motor from Alien and will let you know. Don't really want it yet, still got the Tongxin bike build but thinking ahead. Actually I was chasing up the cutout brake levers I ordered from Alien.

BM

 

[The Maestro]

It is a shame the Alien do not sell the motor alone or built into a wheel. Currently you can only get the motor in a complete kit. I have asked if it is possible to get just the motor from Alien and will let you know. Don't really want it yet, still got the Tongxin bike build but thinking ahead. Actually I was chasing up the cutout brake levers I ordered from Alien.

BM

I think he may sell you a motor alone. I enquired a while ago about getting a 36V version of the 20" wheel motor. At the time he was only selling kits with the 24 Volt version. Anyway he said that he'd be getting some 36V motors in later in the year and that the price would be about 60 pounds. I've not noticed him ever having moved onto the 36V version on the 20" wheel though. I think maybe he's backing off from the 36V kits because of the battery problems, I've certainly only really seen him advertising the 24V versions on everything lately.

 

[The Maestro]

eZee Li-ion battery
.

After dismantling it a bit more it looks a bit different to that battery. There aren't any exposed PCBs, the battery management seems to be incased in a solid metal block with a row of wires coming out of it. Strangely its started outputing its normal fully charged voltage of about 41V now even though I haven't done anything. Maybe it just needed to dry out.