Waiting for the intial charge to finish.....(18Ah Kalkhoff battery)

[10mph]

So now I am experiencing the flaw in the battery driven electric transport concept - the time spent waiting for the battery to charge.

My brand new Kalkhoff Agattu 3G arrived at 0817 this morning. I had had the 8Ah battery replaced with one of the new 18Ah batteries.


By 0845 I had the battery on charge. My watt meter showed it was taking 60 watts from the mains. If I guess that the charger + charging process is 75% efficient, then there must be 1.667 amps going into the battery if at 27 volts.

The 18Ah battery will take about 10 45 mins to charge, before I can try the bike. Sod this, I had better fix up the bike for measuring and try it out under pedal power alone.

Here you see I have mounted the geared Jones Counter on the front axle and made a bodge so it will turn the gear as the front wheel turns. The rev counter will read about 26 counts per revolution of the front wheel. So 1 count will correspond to 10.9 cm forward movement of the bike.

My GPS will record my route and also acts as a real time speedometer. The digital thermometer records the temperature, which affects the tyre circumference and hence the calibration of the Jones Counter. I moved the Klickfix handlebar adapter from my old push bike to the new one, so my notebook is held in a convenient position.

Fixing up that took me about 3 hours, and the first light on the battery had only just switched from flashing to steady. 4 more lights to go, so at this rate the battery won't be charged until dark. I could not wait any longer to try the bike. It would just have to be unassisted pedal power. So over the next hour I did 6 miles on almost flat roads, and got some good calibrations of counts per km using a calibration course which I have laid out nearby.

It is quite windy today, so I am little slow into the wind. But with the wind on my aft quarter I found 10 mph very comfortable. Coming back I took in a short hill, and my speed dropped to about 5 mph in 1 st gear. Despite the extra weight of the bike compared with my push bike, I got up the hill quite as normal even though I have nothing like the gear range of my 21 speed push bike. Coming down the other side the bike's front and aft suspension soaked up the bumps and at 17 mph I could ride safely over the bumpy part of the road, rather than having to follow the smooth route I take on my push bike. The comfort of the new bike's suspension is a revelation to someone used to the jarring and vibration of an unsprung bike.

So my outing convinced me that if I ever do manage to run this big capacity battery flat I shall be able to get home unaided.

Now, how is that battery getting on:
08:45 - put on charge after a few minutes first light starts flashing. (It was a bit disconcerting that there were no lights at first but I saw 60 watts going in, so assumed all was OK.)
11.25 (2 hr 40 mins elapsed) first light steady - 2nd light start to flash
13.25 (further 2 hr elapsed) 2nd light steady - 3rd light flashes
15.15 (further 1hr 50 mins elapsed) 3rd light steady - 4th light flashes
17.08 (further 1hr 53 mins elapsed) 4th light steady - 5th light flashes
18.48 (further 1hr 40 mins elapsed) 5 lights on steady. There is 66 watts still being taken from the mains. The manual implies I have to wait for the lights to go out for full charge. Presumably the lights are measuring battery voltage and 5 lights is Voltage when fully charged but with no charging current flowing. So there is further charging required.

I still can't see that it will be charged before dusk. So it will have to be an early ride tomorrow morning to test out the bike under power.

At about 2020 the wattage started ramping down, as the charge level was "topped off". here is the ramp down recorded time and watts

circa 20:15 - 67 watts
20:10 -51 watts the 5 lights had been illuminated for 1 hr 22min when this ramp down commenced
20:32 - 36 watts
20:39 - 31 watts
20:42 - 29 watts
20:47 - 26 watts
20:52 - 24 watts
20:55 - 22 watts
20:59 - 7 watts All five lights went out at this point. The 7 watts is just the charger idling power.
THE BATTERY IS FULLY CHARGED AFTER 12 hours 14 minutes (Initial Charge)

I know it has been said before, but wouldn't it be great to have standardised batteries and a national network of exchange stations. There would be no waiting for charging then.

 

[lemmy]

I don't know about the 18ah battery but the 10ah one on my Kalkhoff is not fully charged until it has been on for one hour after the battery charge lights go out according to the handbook.

Leave yours on charge, should be nicely charged up and ready for a ride next September

Seriously, I'd be interested in progress reports on your battery.

 

[10mph]

I don't know about the 18ah battery but the 10ah one on my Kalkhoff is not fully charged until it has been on for one hour after the battery charge lights go out according to the handbook.

Oh, so you think I should leave it on longer. 7 watts from the mains for an hour would not add much even if it as actually going into the battery. The manual I have, such as it is (refers only to 10 and 12 Ah batteries), is a 50 cycles translation of a German manual. It makes no mention of your 1 hour period after the lights go out. It just says fully charged when the lights go out.

I think I will assume it is fully charged now, unless you are sure my manual is wrong.

Now to plan how to get rid of some 468wh tomorrow: I think I will have to use the high power mode to do it in a reasonable time.

 

[stevebills]

I would get a fast charger

 

[NRG]

When the lights go out it's charged. Your tale 10mph reminds me of why I'll probably stick to the 10 or 12 Ah battery...I'm also surprised it did not come with at least some charge in it...bad form it being delivered completley flat and also a bit concerning regarding life as Lithium batteries should not be stored flat...

 

[rayschooks]

Hi,
I am very interested to hear how you get on with your new bike and its battery. You would hardly expect the battrey to take that long to energise in subsequent charges?
I cant believe the suggested range of 140Km -I know that this is probably for a 10st super fit cyclist on a completely flat & smooth German test track but its still a pretty impressive stat.
My local bike shop has just recieved an Aggattu C8 and they have very kindly charged the battery. I had a look at it today and I going in for my very first ride on an electrically powered bike tomorrow morning.

The Kalkhoff totally smacks of quality and looks as if it could cope with my considerable frame. Not cheap though but I suppose you get what you pay for?

cheers
Ray

 

[tillson]

I too am surprised that the battery was delivered with such a low state of charge.

I wouldn't worry about the length of time that it takes to charge from a deeply discharged state. I would imagine that you won't be fully discharging the battery too frequently.

Also, if it was my battery, I wouldn't fully charge it unless I needed the full range from the battery. Keeping the charge below 100% could help with battery life. I would think that for most trips out of around 10 miles, you could keep the charge a bit either side of 50%.

 

[JamesC]

I too am surprised that the battery was delivered with such a low state of charge.

I wouldn't worry about the length of time that it takes to charge from a deeply discharged state. I would imagine that you won't be fully discharging the battery too frequently.

Also, if it was my battery, I wouldn't fully charge it unless I needed the full range from the battery. Keeping the charge below 100% could help with battery life. I would think that for most trips out of around 10 miles, you could keep the charge a bit either side of 50%.

Do we know yet if the German made BMZ battery contains exactly the same Battery Management Software as the Japanese made Panasonic battery ?

With the Japanese battery, it is worth remembering that the battery does not enter Deep Sleep Mode until it has discharged to 50%, and sat below 50% for 2 weeks.

I believe that it would be normal for a new Panasonic battery to be delivered "asleep" with a little less than 50% charge on board.

The manual states that a battery that is charged to 100% will take at least 4 months to self-discharge down to 50% before triggering the 2 week timer to enter sleep mode.


Regarding the 18Ah German battery, I was shown a recently manufactured battery whilst visiting Germany a couple of weeks ago.

It was pointed out to me that since the start of 2011, BMZ now include the date of manufacture on the battery label in an open format of Week Number and Year.

James

 

[tillson]

Do we know yet if the German made BMZ battery contains exactly the same Battery Management Software as the Japanese made Panasonic battery ?

With the Japanese battery, it is worth remembering that the battery does not enter Deep Sleep Mode until it has discharged to 50%, and sat below 50% for 2 weeks.

I believe that it would be normal for a new Panasonic battery to be delivered "asleep" with a little less than 50% charge on board.

The manual states that a battery that is charged to 100% will take at least 4 months to self-discharge down to 50% before triggering the 2 week timer to enter sleep mode.


Regarding the 18Ah German battery, I was shown a recently manufactured battery whilst visiting Germany a couple of weeks ago.

It was pointed out to me that since the start of 2011, BMZ now include the date of manufacture on the battery label in an open format of Week Number and Year.

James

That is a good point about drawing comparisons and making assumptions about the BMZ battery based on our experience of the Panasonic model. It could, as you point out, have a different BMS, chemistry and other characteristics.

I think 10MPH has highlighted a minor difference in that the LED flashes at the beginning of each stage of charge.

 

[JamesC]

That is a good point about drawing comparisons and making assumptions about the BMZ battery based on our experience of the Panasonic model. It could, as you point out, have a different BMS, chemistry and other characteristics.

I think 10MPH has highlighted a minor difference in that the LED flashes at the beginning of each stage of charge.

Yes; although the 18Ah battery is physically wider than the 10/12 Ah Panasonic, it feels very similar in weight, so I assume that it must be a different chemistry.

James

 

[morphix]

So now I am experiencing the flaw in the battery driven electric transport concept - the time spent waiting for the battery to charge.

My brand new Kalkhoff Agattu 3G arrived at 0817 this morning. I had had the 8Ah battery replaced with one of the new 18Ah batteries.
View attachment 1935

By 0845 I had the battery on charge. My watt meter showed it was taking 60 watts from the mains. If I guess that the charger + charging process is 75% efficient, then there must be 1.667 amps going into the battery if at 27 volts.

The 18Ah battery will take about 10 45 mins to charge, before I can try the bike. Sod this, I had better fix up the bike for measuring and try it out under pedal power alone.
View attachment 1936
Here you see I have mounted the geared Jones Counter on the front axle and made a bodge so it will turn the gear as the front wheel turns. The rev counter will read about 26 counts per revolution of the front wheel. So 1 count will correspond to 10.9 cm forward movement of the bike.

My GPS will record my route and also acts as a real time speedometer. The digital thermometer records the temperature, which affects the tyre circumference and hence the calibration of the Jones Counter. I moved the Klickfix handlebar adapter from my old push bike to the new one, so my notebook is held in a convenient position.

Fixing up that took me about 3 hours, and the first light on the battery had only just switched from flashing to steady. 4 more lights to go, so at this rate the battery won't be charged until dark. I could not wait any longer to try the bike. It would just have to be unassisted pedal power. So over the next hour I did 6 miles on almost flat roads, and got some good calibrations of counts per km using a calibration course which I have laid out nearby.

It is quite windy today, so I am little slow into the wind. But with the wind on my aft quarter I found 10 mph very comfortable. Coming back I took in a short hill, and my speed dropped to about 5 mph in 1 st gear. Despite the extra weight of the bike compared with my push bike, I got up the hill quite as normal even though I have nothing like the gear range of my 21 speed push bike. Coming down the other side the bike's front and aft suspension soaked up the bumps and at 17 mph I could ride safely over the bumpy part of the road, rather than having to follow the smooth route I take on my push bike. The comfort of the new bike's suspension is a revelation to someone used to the jarring and vibration of an unsprung bike.

So my outing convinced me that if I ever do manage to run this big capacity battery flat I shall be able to get home unaided.

Now, how is that battery getting on:
08:45 - put on charge after a few minutes first light starts flashing. (It was a bit disconcerting that there were no lights at first but I saw 60 watts going in, so assumed all was OK.)
11.25 (2 hr 40 mins elapsed) first light steady - 2nd light start to flash
13.25 (further 2 hr elapsed) 2nd light steady - 3rd light flashes
15.15 (further 1hr 50 mins elapsed) 3rd light steady - 4th light flashes
17.08 (further 1hr 53 mins elapsed) 4th light steady - 5th light flashes
18.48 (further 1hr 40 mins elapsed) 5 lights on steady. There is 66 watts still being taken from the mains. The manual implies I have to wait for the lights to go out for full charge. Presumably the lights are measuring battery voltage and 5 lights is Voltage when fully charged but with no charging current flowing. So there is further charging required.

I still can't see that it will be charged before dusk. So it will have to be an early ride tomorrow morning to test out the bike under power.

At about 2020 the wattage started ramping down, as the charge level was "topped off". here is the ramp down recorded time and watts

circa 20:15 - 67 watts
20:10 -51 watts the 5 lights had been illuminated for 1 hr 22min when this ramp down commenced
20:32 - 36 watts
20:39 - 31 watts
20:42 - 29 watts
20:47 - 26 watts
20:52 - 24 watts
20:55 - 22 watts
20:59 - 7 watts All five lights went out at this point. The 7 watts is just the charger idling power.
THE BATTERY IS FULLY CHARGED AFTER 12 hours 14 minutes (Initial Charge)

I know it has been said before, but wouldn't it be great to have standardised batteries and a national network of exchange stations. There would be no waiting for charging then.

Blimey, 12 hours charge is long time to wait, but with the battery that size you will be charging it far less frequently than most, depending on how far you ride of course.. My little 5Ah battery takes 3 hours to charge which comes in rather handy when I need to go from flat to full quickly. I find myself charging it once a week at the moment, as I'm only using the bike for short 20 mins rides each day for exercise..

 

[NRG]

Differences in battery management aside it dosent change the fact that it was delivered 'flat'...maybe it's nothing to worry about, however, it's a little concerning if these batteries are kept in this state for longish periods before delivery. Even with advanced sleep modes in the BMS some charge should still have been present.

 

[rog_london]

Differences in battery management aside it dosent change the fact that it was delivered 'flat'...maybe it's nothing to worry about, however, it's a little concerning if these batteries are kept in this state for longish periods before delivery. Even with advanced sleep modes in the BMS some charge should still have been present.

Not necessarily - it does depend entirely on the exact technology used.

Back in the days of early NiCds they were always supplied flat - not a peep out of them until they'd been charged for the first time.

If these new batteries are designed to be stored flat so much the better - it makes for a long stress-free shelf life, and also means that you probably don't need to bother 'looking after' them over the winter if you're not riding. Also it's a much safer bet while they're being stored and transported in bulk if there isn't a huge concentrated stored energy 'bomb' being moved around.

I would suggest that might be looked on as 'progress'!

It doesn't sound as though any harm has come to it though, in view of the time taken to charge it - certainly no loss of capacity. Maybe subsequent charges might be a good deal quicker now the battery has been woken up. No doubt 10mph will let us know about those subsequent charges. After all, that's what really matters, not the first charge.

Rog.

 

[stevebills]

I love the mobile office thing you have going on with the arrows ponting it made me giggle ( nearly wet myself )

 

[rayschooks]

Pardon my ignorance but why have all the gizmos etc on the front of the bike? Surely a decent cycle computer would tell you how far you have travelled + speed etc?

I have used this site, which is attached to google maps that allows me to plan my routes ahead of time.

[URL="http://www.daftlogic.com/projects-google-maps-distance-calculator.htm

 

[stevebills]

I think its a temp measure m8... no 1 in the right frame of mind wud cycle like that unless 4 a bet

 

[10mph]

First ride

The first discharge was not as lengthy as the first charge.

I set out at 7.15 this morning. I selected max assist since I wanted to run the battery down as quickly as possible.

My first task was to calibrate the circumference of my front wheel by riding back and forth along a very accurately measured 500 metres. The front wheel rev counter told me how many wheel revs in 500m (accurate to about 1/25 of the wheel rev). I then rode a rather flat road running course which I and others had previously measured. The course came out to within about 2 feet of what I believe to be the exact distance. This was a very good result and shows that an electric assist bike can be used in the same way that a push bike has been traditionally used to measure the length of road running course.

Next to test the bike on hills and for range, I headed off to a local hill. The steepest gradient peaks at 13% for about 200m. I can only just get up on my push bike. In 1st gear on the Aggatu 3G (C3) I went up at around 4.5 mph on the steepest part. This is roughly 3 times my speed on my push bike. This is exactly what I hoped that the 3 speed Aggatu would achieve. Since I am unlikely to encounter hills steeper than this, the first gear is low enough for my needs. Normally I keep my speed down to 10 mph and top gear on this bike suits this speed well. So for my limited purposes I have no need for the more expensive 8 gear model of the Aggatu.

There are 5 different routes up this hill all needing 1st gear, so I tried then all out. For good measure I did two more trips up the 13% route. Then I did another long hill. In all I climbed 435m = 1427 feet, measured using contours on an OS map (ignoring minor bumps along the route). By the time I reached home only the last light on the battery was on, so I did loops round a nearby park until the handle bar indicator started flashing, and after a further half mile the battery light also started flashing, and I headed home. According to the manual the commencement of flashing on the lowest battery light indicates 10% of capacity left

In all 35.1 miles travelled in 3 hours 41 mins at an overall average speed of 9.5 mph. But this included many stops to read the battery, adjusting the seat and handlebars, both of which worked loose, etc. So the bike easily meets the spec given in my signature line.

If I went onto eco mode, with the motor contribution reduced from 200% of my power to 50% of my power, and picked a less hilly route, then the label on the battery which indicates upto 140 km = 87 miles does not look unreasonable.

I am following this recommendation of Flecc for battery conditioning:

To condition the battery it should first be fully charged, then used until almost empty, and for a new battery this process should be repeated twice. For the first of these conditioning cycles the usage can be down to the first slow flashing stage shown on the handlebar meter, but it's important that the second conditioning usage is down to the second and fast flashing stage for the meter zero to be correctly reset.
​

So the battery is now back on charge. I will report in due course on the second cycle of charge/ discharge.

In answer to various points on this thread:

rayshoocks: I hope your first ride on an electric bike will be as enjoyable as this ride on my first e-bike.
Concerning my gizmos - all useful for my application - measuring the length of road running courses. Googlemaps are good, but not good enough to give 0.1% accuracy.

JamesC: I cant decode the manufacture date. The battery label says,
Derby Cycle
Li-ion 25,2V / 453.6Wh
GEB 11-W3 / Art: 14069 / F100152
S/N 0021178 made in Germany
Derby Cycle Werke GMBH 18Ah

 

[JamesC]

JamesC: I cant decode the manufacture date. The battery label says,
Derby Cycle
Li-ion 25,2V / 453.6Wh
GEB 11-W3 / Art: 14069 / F100152
S/N 0021178 made in Germany
Derby Cycle Werke GMBH 18Ah

GEB 11-W3 = Made in Week 3 of 2011

James

 

[10mph]

GEB 11-W3 = Made in Week 3 of 2011

Thanks. So it is about 10 or 11 weeks since manufacture. Could they be sent out without ever being charged?

 

[rayschooks]

I think I have seen the bike for me - Agattu C8. I was very interested in your thread as it has the same battery as yours. I had a go on it today - took it up the nearest decent hill. Im an 18st ex prop forward (rugby) and the bike got me up the hill without a problem even though I dont think I was really getting the best out of it

The shop owner is giong to let me have it for a day or two next week to see how I get on in my daily commute - pretty decent of him really.

I would like to hear how long it takes for you to charge your battery tonight and if it performs any differently the next time you go out.
Ray