Panasonic Unit Battery Information

[flecc]

I've now gathered all the information on the Panasonic Lithium Polymer batteries and placed it on a webpage on my Panasonic unit website as a convenient reference source. My particular thanks to JamesC for his feedback of experience with three of these batteries.

On the link below, go to "Lithium Polymer Battery" under the "New Type Unit" heading:

Panasonic Unit Index
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[tillson]

Another useful addition to your site. Thank you flecc.

The only thing that I would add, through experience of using these Panasonic batteries, is that the capacity check will tend to drift more frequently if the battery is used in cold weather. Between January and March this year, the capacity check fell to 80% on several occaisons ( I think 4 times). This was restored on each occasion by performing the conditioning cycle as you describe.

Between March and mid October, the capacity check has remained at 100%. Since mid October, it has fallen to 80% again. I have not performed another conditioning cycle as I see no point in doing this because the capacity check will only drift again as the weather turns even colder.

I use a power meter to monitor the amount of charge going into the battery and at this time, the results give me no cause for concern.

 

[JamesC]

Another useful addition to your site. Thank you flecc.

The only thing that I would add, through experience of using these Panasonic batteries, is that the capacity check will tend to drift more frequently if the battery is used in cold weather. Between January and March this year, the capacity check fell to 80% on several occaisons ( I think 4 times). This was restored on each occasion by performing the conditioning cycle as you describe.

Between March and mid October, the capacity check has remained at 100%. Since mid October, it has fallen to 80% again. I have not performed another conditioning cycle as I see no point in doing this because the capacity check will only drift again as the weather turns even colder.

I use a power meter to monitor the amount of charge going into the battery and at this time, the results give me no cause for concern.

Tom
2 of my 3 have also displayed 100% on the capacity check throughout the Summer, having dipped to 80% last Winter.

The 3rd battery is one that I bought earlier this year with a second hand Agattu. It is now a full 2 years old and came back from 3 lights to 5 lights after a full recalibrating cycle around April time. It has remained at 100 % display throughout the Summer, but I am expecting it to lose its registration again soon in the colder weather.

The cold weather always brings a penalty on range of the order of 2 or 3 miles.

James

 

[flecc]

A good point Tom and James, I'll add that in tomorrow when I do an edit on the site. Thanks for the ongoing information.
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[tillson]

The 3rd battery is one that I bought earlier this year with a second hand Agattu. It is now a full 2 years old and came back from 3 lights to 5 lights after a full recalibrating cycle around April time. It has remained at 100 % display throughout the Summer, but I am expecting it to lose its registration again soon in the colder weather.

It's good to hear that the 2 year old battery is holding up. As more and more of these batteries reach the two year mark, we will start to find out how well they perform out of the warranty period.

Regards

Tom

 

[flecc]

Job done. I've added a "Cold Weather Effects" section to the page, together with links to it from "Charge Meter" and "Capacity Check".

I've also added a battery photo to the header to brighten the page:

Battery page
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[Barry Heaven]

Flecc -Thanks for your new section, very useful reference.

You have piqued my interest with "....a prospect of a larger one in the near future". Do you know what Ah rating it will be and will it slot into existing Panasonic units?

 

[flecc]

No more than rumour status at the moment Barry, but there could be a 15 Ah battery. I'm sure it will fit the existing bikes if it appears, partly because Panasonic have suffered from the incompatibility before and partly because so many are now using the present unit, some 17 makes in all at the last count. The fit could be affected by height clearance though, some models having little spare space above.
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[Barry Heaven]

Sounds good. A 50% increase in range! I have the the extra large frame Pro Connect which does leave quite a bit of free space above the battery but I don't know how the smaller frames would fare.

 

[flecc]

They could gain some "free" height by either omitting the handle on top or doing what they did on the early unit NiMh battery, make a recessed folding T handle:

 

[quilly21]

Cold Storage of Batteries

Hi All,
I read sometime back that lithium batteries have a finite life due to oxidisation, this process being reduced at lower temperatures.
The optimum storage condition being 40% charge and low temp if storing for any time.
My question is would keeping the panasonic battery in a fridge after charging and between use be a sensible way to prolong the life of the battery?
I hear encouraging things about the battery life of these panasonic units,
however I was enquiring about one on ebay where the capacity or range had reduced from 42 miles to 17 miles over 2 years on an agutta used for regular commuting.

 

[flecc]

Definitely not cold storage for a battery that's in use, since it would ned to be slowly brought back to ambient temperature every time to work properly again. The part charge/low temperature storage is only when a battery needs to be stored long term, a few months for example. The Panasonic battery already has a unique storage provision, it automatically shuts down after about two weeks of being out of use, preventing further storage discharge, after which it has to be given a full conditioning charge cycle to get it working properly again.

In respect of that loss of capacity mentioned, there are many unknown factors. The whole life can be only two years if heavily used. The capacity metering drifts out over time and has to be reset with a deep conditioning cycle, using the battery until the final fast flashing stage of the last LED. The 42 miles is well beyond the natural range and relies heavily on the human input. An e-bike can make one lazier over time so the rider may be putting in far less pedal effort after two years.

You can see that we'd need to know very much more before passing judgment on that e-bay battery.
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[lemmy]

I'm sure it will fit the existing bikes if it appears The fit could be affected by height clearance though, some models having little spare space above.
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And the locking top bracket fitting, presumably?

I wish they'd put a locking cam on that, too.

 

[flecc]

And the locking top bracket fitting, presumably?

I wish they'd put a locking cam on that, too.

Since that post I made it's confirmed the 15 Ah battery won't fit any existing bikes, it's too wide and needs modified unit housings and cranks.
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