Panasonic Battery Issues

[Mussels]

Just playing around with statistics a bit more (and assuming of course that the seller was not the sort of company which would return the duds to stock!) if a company sold 1500 batteries in a year, I make it that you would expect to see one customer getting a dud first time followed by a dud replacement (ie Tillson's experience), once a year if 39 out of the 1500 were found by customers to be duds. That would be a dud rate of 2.6%.

To be honest, that's probably not too bad a failure rate, and shouldn't, in itself, put people off buying a Kalkhoff. But if Tillson get's a third dud, or more examples emerge of people getting two duds, the failure rate would climb.

It was statistical thinking like this that got some of the questionable cot death convictions, originally the doctors said that the chances of two siblings dying from cot death were so far out that it had to be murder, Lightning doesn't strike the same place twice and all that.
Later on good reasons were found that cot deaths are far more likely to happen in a household where it has happened before, the convictions were overturned.
What I'm trying to say is that we don't know why the batteries failed but once he has one fail then he is much more likely to experience a second failure. For all we know the battery could have been kept next to an ultrasound device which changed the insides, or a microwave oven that leaked microwaves. All very small chances but still important when considering freak statistics.

 

[flecc]

For all we know the battery could have been kept next to an ultrasound device which changed the insides, or a microwave oven that leaked microwaves. All very small chances but still important when considering freak statistics.

Although these are very unlikely, there are some other greater possibilities. The supplied charger might be malfunctioning for example, damaging the battery with too high a charge level before cutout. Another but smaller possibility is the that motor software is discharging the battery to too low a level before cutout, taking the cells below damage level.

If Tillson were to have a third battery fail, testing the charger as well initially would be very advisable since that would be a likely cause of the trouble.
.

 

[Tim]

The supplied charger might be malfunctioning for example, damaging the battery with too high a charge level before cutout.
.

This is now looking like a distinct possibility as candidate for the cause of the problem... we think we know what is and we are investigating further.

 

[tillson]

The supplied charger might be malfunctioning for example, damaging the battery with too high a charge level before cutout.

This point had crossed my mind and I took the charger with me to 50C. I mentioned chargers to Lloyd but he said it was unlikely so it stayed in the car.

When Lloyd handed over the battery, I'm sure he said that it had been fully charged ready for use. When I put it on my charger back home, all 5 LEDs illuminated and it continued to charge for a further hour before they went out.

I'll give them a call and ask for their advice on this one. I assume the cut out circuit is in the charger and not in the battery?

 

[flecc]

I'll give them a call and ask for their advice on this one. I assume the cut out circuit is in the charger and not in the battery?

Normally with lithium batteries the cutout is in the battery so overcharging would only occur if the battery electronics (BMS) were faulty.

The Panasonic system has an important difference though, instead of two connections, three differing active connections between battery and charger and battery and motor, leading me to suspect that the battery management is shared with the BMS by both the motor and charger electronics, giving potentially ideal conditions in both discharge and charge modes. This would be typical of the sort of sophistication Panasonic brings to e-bikes.
.

 

[frank9755]

It was statistical thinking like this that got some of the questionable cot death convictions, originally the doctors said that the chances of two siblings dying from cot death were so far out that it had to be murder, Lightning doesn't strike the same place twice and all that.
Later on good reasons were found that cot deaths are far more likely to happen in a household where it has happened before, the convictions were overturned.

I'm not sure I agree with that!

Just because someone once misused statistics with tragic results does not give you grounds to declare the whole science to be in default. There lies the road to dumbing down. Remember many statistical techniques were developed specifically to predict failure rates in manufacturing processes!

In this instance the fact that one person getting two failures is improbable means that it's necessary to look for another, more likely cause, be it your suggestion of where the bike is kept, returning duds to stock or, the current favourite - charger problems. However if 50 cycles were saying they were had had about 40 duds, or even 100, then it wouldn't be such a surprise one person had had two, and Lloyd would have been right, on balance of probability, to tell him to leave the charger in the car!

 

[styx]

Battery charger fault?

Hi everybody.
I spoke with Scott at 50cycles today and he requested me to return the charger with my faulty battery as they thought the fault could be with the charger being incorrectly wired.So far I am on my third set of gears and now a second battery and the bike has only done a little over one hundred miles,it's turning out to be a frustrating experience this electric biking.

 

[WALKERMAN]

Hi everybody.
I spoke with Scott at 50cycles today and he requested me to return the charger with my faulty battery as they thought the fault could be with the charger being incorrectly wired.So far I am on my third set of gears and now a second battery and the bike has only done a little over one hundred miles,it's turning out to be a frustrating experience this electric biking.

You have been really unfortunate but I'm sure that 50Cycles will sort it out for you very quickly.
I got my replacement battery from them within days.
I had problems with the charger not working sometimes but I used a different adaptor plug and I think that may have solved the problem.

 

[HarryB]

This is now looking like a distinct possibility as candidate for the cause of the problem... we think we know what is and we are investigating further.

Can you keep us posted about the charger issue? As I also had an early failure I wonder if there is a dud batch of chargers causing the battery failures. I cannot claim to have used the Agattu much with the new battery but I don't want to damage it if I have a faulty charger.

 

[bogmonster]

I did buy a lottery ticket last Saturday as you suggested and this was the first one for many years.

I lost. Is this a good or a bad thing?

ps You owe me a quid for giving me bad advice

The pound is in the post....

 

[tillson]

Lloyd from 50C has just contacted me to arrange to swap my charger. It's good to know that they are taking this seriously and investigating this issue.

 

[WALKERMAN]

I got home this evening and put the battery on the charger and plugged it in to the other adaptor plug I mentioned earlier - nothing.
I tried it several times but still not a flicker.

I then put the 2 pin plug back in the original adaptor plug and it worked.

I never know if it will work, and simply by opening up the adaptor plug and fiddling with the fuse holder and the 2 pin plug will it then work. This is very annoying.

 

[flecc]

I got home this evening and put the battery on the charger and plugged it in to the other adaptor plug I mentioned earlier - nothing.
I tried it several times but still not a flicker.

I then put the 2 pin plug back in the original adaptor plug and it worked.

I never know if it will work, and simply by opening up the adaptor plug and fiddling with the fuse holder and the 2 pin plug will it then work. This is very annoying.

I couldn't see your previous reference to the other adaptor plug. Why were you using it, was the 50cycles supplied original playing up?
.

 

[wotwozere]

Hi

Try using the next socket it worked with my Microwave.

Thx

bob

 

[WALKERMAN]

I couldn't see your previous reference to the other adaptor plug. Why were you using it, was the 50cycles supplied original playing up?
.

Yes.
I changed the fuse first time it happened and it worked.

The next time it happened was a few weeks later and I opened it up and just moved the fuse and wiggled the 2 pin plug. It worked!

The same thing has happened about 8 times in 6 months.

This most recent event as I said, I used a different style adaptor plug and it worked.

Then the next charge the following day it didn't work. So I opened it up and wiggled everything again and it worked!

I' wondering now if it might be a poor connection in the 2 pin plug.

 

[flecc]

I' wondering now if it might be a poor connection in the 2 pin plug.

This was the reason for my query, I thought it very likely that there's a poor connection in there, dry joint or fractured wire giving an intermittent connection.

Hard wiring to a 13 Amp plug would be the answer, making sure the connections were correctly placed, important on this unit. Check with 50cycles before doing that though, since it might affect your warranty.
.

 

[tillson]

I have just received a new charger from 50C (my third) and it too appears to be intermittent with regards to whether it is going to charge the battery.

The first charger that I had supplied with the bike back in July was hit and miss with regards to whether it would charge. It had a Wilkos plug on it complete with 67p price sticker. I stripped the plug down, changed it for another, tried allsorts but it had a mind of its own. Unfortunately it was more miss than hit and was totally unreliable.

50C changed that first charger and the second one worked every time. However that has now been swapped for a third charger as a result of my battery problems. This latest model has a plug within a plug. Something I have never seen before. It looks like a standard UK 13 amp plug with another plug going into it where the flex usually goes.

I have just put my discharged new battery on it after its first conditioning run and nothing happened. No amount of wire wiggling would make the battery charge. I have just carried it up the drive and plugged it into the house supply and it is working.

An interesting thing that I noticed with the first charger was that once I had managed to get the battery to charge, I could lift it of the charger partially charged, leave it a few days without using the battery and when I put it back on charge it would continue charging without exception. If I used the battery on the bike, ie discharge it to some extent, then I would nearly always have problems getting it to re-charge again. I don’t know if this is significant.

The new charger seems to be behaving in a similar fashion to the first to some extent. Now that I have the battery in a charge mode, it continues to charge even if I lift it off, put it back on again etc. It is now back in the garage charging quite happily. We’ll see what happens after I discharged it a little.

 

[tillson]

Hi

Try using the next socket it worked with my Microwave.

Thx

bob

Bob, what are you trying to say here? Many of your posts don't appear to make much sense to me and I don't think that I am alone in this thought.

I find this forum very useful and get a lot out of it. You are starting to spoil it with some of the posts, particularly when you rake up old spent threads at the expense of current issues.

Please stop. You are starting to grind my pipe!

Kind regards

Tom

 

[Mattyduk]

reading this thread, along with chain/gear issues with the Kalkhoff bikes, has got me a bit uneasy, as I've just recently (pre xmas) bought a new Pro-Connect.

I would be very unhappy if after a 1000 miles it exhibited any of these faults, let alone a 100.

No problems so far on the pro-connect (touch wood), apart from having to change the fuse of the charger plug when it arrived. So far it's an absolute stunning bike - superb range, hill climbing, looks and control.

 

[PED-AL]

Bob, what are you trying to say here? Many of your posts don't appear to make much sense to me and I don't think that I am alone in this thought.

I find this forum very useful and get a lot out of it. You are starting to spoil it with some of the posts, particularly when you rake up old spent threads at the expense of current issues.

Please stop. You are starting to grind my pipe!

Kind regards

Tom

I second that !!