Panasonic Battery Issues

[tillson]

From my experience I found it made no difference whether the battery was charged or mostly discharged, I would still get the 3 lights with the 10 sec test. Having said that it makes sense to check it with a fully charged battery.

I had the same experience. 4 lights during the test regardless of charge state.

 

[WALKERMAN]

Hi Walkerman

What is your name so I can pull up the invoice, worst case send it back to us for exchange.

I think people are panicking a little bit regarding these batteries to put it in context out of 1500+ Batteries we have claimed 6 under warranty, that is 0.39% return in 13 months of selling this battery. As a Distributor we are very happy with that and know that Panasonic make over 400000 of this type of battery for Electric bikes so changing a few batteries under warranty is no major crisis.

Panasonic have done years and years of testing to get to this point, they are not being researched and developed by customers like on some other makes of Chinese bikes on the market.

All we ask is people to send them to us so we can exchange them underwarranty. However the 2 year warranty on a battery does not refresh after we send you a new one the warranty stand from the date of purchase or delivery of your bike if ordered on back order.

Finally we sold 150 bikes in 2004 of this same battery and only now are people looking for a new battery, we did not hear from any Will bike owners until this year 2008.

When you sell volume of anything there will be returns so please stop panicking, if you have a faulty battery it will get swapped underwarranty.

Best regards

Scott

I'm not panicking.

This website is used by ebike owners for discussion and that is exactly what has been going on.

 

[flecc]

Panasonic have done years and years of testing to get to this point, they are not being researched and developed by customers like on some other makes of Chinese bikes on the market.

Scott

While agreeing with you about Panasonic batteries of all types for which I have the highest regard, I see little wrong in well over 1000 customers getting free £350 batteries to test for life as in one Chinese bike example. I'm sure all e-bike customers would be delighted to have such a benefit.
.

 

[Andyj]

Excellent Service

Well I have been off the road for the past week due to sending my battery back to 50Cycles; could not believe how much I missed riding my Agattu.

As much as some of us might be a little dissappointed with problems with our batteries, I can only state from my own personal experience what excellent aftersales service I have received from 50Cycles; as soon as the problem was confirmed by Mark a replacement was dispatched under warranty.

I certainly hope that further diagnosis may indicate the nature/cause of these failures; fingers crossed.

Best Wishes to 50Cycles

Andy

 

[musicbooks]

a discharge moment

A rather strange ( and possibly worrying) thing happened to the battery power yesterday. ( agattu bike, panasonic battery). Fully charged (as usual) I set off on my normal commute. About 1.5 miles into the journey and half way up one of my very steep hills, the battery indicator on the bike sudenly plunged to one light and flashing. I made it up the hill OK. On my return leg, I kept the battery swiched off until I reached the second hill on my commute. Power lasted until I got home. I recharged the battery ( one light flashing ) and after about 2.5 hours went to check on progress. Three continuous lights were now showing but as I looked, the lights suddenly leapt up to full charge. I continued charging until all lights went out.

Worth noting that I keep the battery in the house and it hasn't been anywhere near as cold as the last couple of weeks.

Today, after the first leg of my commute, all seems well, all lights remain lit as usual ( I ran a check and all cells appear fully charged).
I'll report again on the battery's conditon when I get home tonight.

What could this be?
bw
musicbooks

 

[tillson]

Hi Musicbooks

Have you done the diagnostic capacity test? I couldn't work out from your post if you had or not.

Just to remind you in case you have not done the test, this is what I believe is the correct procedure:

1) Make sure the battery is fully charged. (Don't know if this makes any difference, but apparently it is what we should be doing.)

2) Press and HOLD in the battery test button in.

3) Initially the LEDs will illuminate to indicate the charge status. (KEEP HOLDING THE BUTTON IN)

4) All the LEDs will go out momentarily and will then illuminate again after about 10 seconds of sustained button pressing. If the battery is in good condition all 5 should light up. This second display of LEDs is not showing charge status, but battery capacity. I believe that each LED represents 2 Amp Hours. 5 LEDs being 10 Amp Hours, anything less indicating a reduction in battery capacity (eg 3 LEDs = 6 Amp Hour)

Sorry if you already knew this.

ps. I have had a replacement battery under warranty and this new one behaves in a very strange way compared to the original.

On a full charge, the bike will travel 12 miles before the first LED goes out on the handlebar indicator. The second one is out within 4 miles of the first and the final LED is flashing at 1 Hz before reaching 20 miles. The bike will continue to operate on 1 flashing LED to around the 40 mile mark. That is 50 % of the power being provided whilst one LED is flashing.

I found this out whilst doing the two conditioning runs on the new battery. I have not discharged it so completely again, but on my 18 mile commute things seem to be following a similar pattern. I'm not too worried as the battery gives me that range that I expect and the above test indicates 10 Amp Hour.

I just thought I would mention this as your discharge profile might be similar to mine and hopefully you will have nothing to worry about.

(The bike is a Pro Connect with the standard 23 tooth sprocket and always used in medium power setting.)

Tom

 

[flecc]

Tom, it may have been an overload due to the climb causing a safety restriction in the battery management system, this more likely at lower winter temperatures which impair the battery efficiency.

That said, these battery meter systems are not particularly accurate and can do odd things at times. They work by measuring minute changes in voltage and to do that the circuit has to be an extremely sensitive one. It follows that a very small irregular variation in the supply can cause an unduly large indication on the meter.

These same metering inaccuracies used to crop up on the earlier Panasonic systems which used NiMh batteries, the cause again being the meter circuit high sensitivity rather than serious faults.
.

 

[tillson]

Thanks Flecc. It could well be what you are suggesting. I'm not too worried about my new battery because it is delivering what I expect in terms of range on a standard setup and the diagnostic is indicating that all is well.

Hopefully, the same will apply to Musicbooks' situation.

Regards

Tom

 

[musicbooks]

Tom, it may have been an overload due to the climb causing a safety restriction in the battery management system, this more likely at lower winter temperatures which impair the battery efficiency.

That said, these battery meter systems are not particularly accurate and can do odd things at times. They work by measuring minute changes in voltage and to do that the circuit has to be an extremely sensitive one. It follows that a very small irregular variation in the supply can cause an unduly large indication on the meter.

These same metering inaccuracies used to crop up on the earlier Panasonic systems which used NiMh batteries, the cause again being the meter circuit high sensitivity rather than serious faults.
.

Thanks Tony,
Sound advice as ever.. I will monitor tonight again and over the next few days, and see what happens.

Thanks Tom too for your advice on checking battery capacity.

Best wishes,
Tom
musicbooks

 

[musicbooks]

After a recharge and another day's commute, all seems well again with the battery. I ran a systems check and all cells fully functioning.

Flecc, your diagnosis would appear to be correct ( strange that )

bw
musicbooks

 

[flecc]

After a recharge and another day's commute, all seems well again with the battery. I ran a systems check and all cells fully functioning.

Flecc, your diagnosis would appear to be correct ( strange that )

bw
musicbooks

. Funny old things batteries, especially in the cold, and the meters that purport to say what's in them are often even more odd. Once used to them, on my bikes I always ignore any meters fitted, use the computer trip recorder at each charge and go by mileage covered.
.

 

[musicbooks]

Thanks Tony,
I'll keep an eye on it though and report any further strange goings on..

bw
Tom

 

[tillson]

My battery seems to have settled down now and the discharge is much more linear. This seems to have coincided with the weather turning milder around here. It was +9 degrees on my way to work and +7 on the way home last night. The battery is now behaving as it did in July when the bike was new

 

[flecc]

My battery seems to have settled down now and the discharge is much more linear. This seems to have coincided with the weather turning milder around here. It was +9 degrees on my way to work and +7 on the way home last night. The battery is now behaving as it did in July when the bike was new

I'm not surprised. As I've often remarked, batteries are chemical devices and lab practice shows what that means. We often warm test tubes over Bunsen burners to achieve chemical activity, but never plunge them into iced water for the same ends. Essentially batteries desire 20 to 30 degrees C for optimum working efficiency, and anything approaching zero degrees is very bad news indeed.
.

 

[WALKERMAN]

Pro Connect Battery

Just to let the forum know that the faulty battery I had was replaced by 50C within days of them receiving it.

 

[burncycle]

Just to let the forum know that the faulty battery I had was replaced by 50C within days of them receiving it.

Thats good news.
Did you have another bike to use?
When my bike was in for repair I didnt know how much I missed it.
I actually hated going to work in the car for the week.
Its amazing how the bike gives you a buzz.

Is the new battery OK?

Regards Bob.

 

[WALKERMAN]

Thats good news.
Did you have another bike to use?
When my bike was in for repair I didnt know how much I missed it.
I actually hated going to work in the car for the week.
Its amazing how the bike gives you a buzz.

Is the new battery OK?

Regards Bob.

Yes, I had to get out my 3 year old Giant Lafree Twist ST. Charged the battery and it was up and running without any problems after standing idle for the past 5 months. It certainly was (still is) a classic bike and oozes quality. It is a pity Giant didn't develop it along the lines of the Kalkoffs - I'm sure they would have had a winner.

I will report on the new battery over the next five or six months to see it doesn't go the same way as the origional.

 

[tillson]

Oh **. My second battery is on the way out. I religiously ride the same route to and from work every day. My first battery lost over 20% of its capacity in fewer than four months of usage and was replaced under warranty by 50 Cycles without any problems.

The bike (a Pro C) is now just under 6 months old and the replacement battery has followed exactly the same capacity loss profile as the first. I have been watching the charge indicator lights go out earlier and earlier on the route that I use. Tonight, the outside air temperature is higher than it has been for a few days (+4), but the battery was nearly exhausted when I arrived home. I have been getting home with two out of the five battery lights illuminated a while back whilst riding in temperatures as low as minus four. According to what I read on here, because the temperature is higher today (+4), the battery should be performing better than it did when it was minus 4. The reverse is true, I am actually getting less range.

I have carried out the battery diagnostic check and it is indicating that the battery has lost over 20% of its capacity. This is really worrying me. I was prepared to give the first battery the benefit of the doubt but I am beginning to think that this is how these batteries are. About a 20% capacity loss per 700 miles. At £300 a shot this is not a cheap way to get around. This just isn't viable once the guarantee runs out.

I really do hope that I have just picked up a couple of rouge batteries, but I must say that I am now having doubts.

I will call 50 C tomorrow. It looks like another haul down to Loughborough or a trip to the post office and a few days in the car for me.

 

[flecc]

Sorry to hear this tillson, but it seems to be an exceptional coincidence, judging by the many Agattu and Pro Connect bikes used for commuting and other daily use, often on quite high mileages. These same batteries are used on the more powerful high speed versions by BikeTech and now by the similar Pro Connect S, so they should withstand hard work.

Hopefully you won't have to wait long for a replacement and that will break the mould for you.
.

 

[tillson]

Thanks for the reassurance Flecc. I know these batteries are used in a growing number of applications so I am clinging to the notion that if they were no good, their usage would be shrinking not growing. I am just really disheartened that this new battery has failed in exactly the same manner as the first.

Right from the outset I had a feeling that this would happen. I have not been 100% happy with the replacement battery from day one. It behaved very strangely to begin with, settled down for a while and then commenced the depressing gradual loss of capacity. Oh well third battery lucky!