Mercedes-Benz Hybrid Electric Bike (battery woes)

[Blew it]

Projem:

When reading your first posting.

I 'right-clicked' the dreaded red cross and copied the URL from 'properties' into IE. This took me to your Flicker page where I selected medium size image at 640 x 284 and 'right clicked' that to get the image code ( URL ) in 'properties'.

To post them in the reply, I clicked the 'yellow mountain' icon and pasted the image code into the dialogue box, you may get an alert with your browser, click the yellow bar that appears and 'temporarily allow scripted windows' , click the yellow mountain again and then paste the code into the box. click 'OK'

After you have prepared a posting, click on 'preview post' first, this will show you exactly what will appear on the forum ( What You See Is What You Get ). If you need to make changes, this is done in the text window below the preview window. After making the changes, click 'Preview Post' again. If everything is alright, click 'Submit Reply'.

When posting images on the forum, please keep the images to no larger than 800 x 600, anything larger invokes the scroll bars on viewers screens.

Have fun
Bob

 

[projem]

Thanks Bob

Thanks for the explanation Bob and for posting the pictures.

 

[projem]

Thanks flecc

Yes, that Powerstream charger is a generic one, the thermistor values (R=10K and B=3950) happening to nearly match the thermistor in the Giant Lafree NiMh battery, but without knowing the thermistor values in the Mercedes battery pack, it can't be absolutely guaranteed to work correctly.

However the thermistor in the cell pack for the Mercedes bike can be changed and a suitable replacement NTC thermistor is Radiospares RS 151-237. The characteristics are R = 10k, B = 3914.

If all else fails, the thermistor can be replaced by an ordinary 10 k resistor since the charger has a Vmax cut-off as well.
.

Is there an easy way to check the motor and batteries before spending money on a new battery pack and charger?, Im assuming/guessing the Ni-Cads are defunct after 10 years despite 1 or 2 charges, but cant tell without a charger to test both. Thanks for any replies.

 

[flecc]

The NiCads will certainly be dud now, even if they accept any small charge it will collapse as soon as you try to
draw from it. Not knowing that motor and controller I can't suggest any way of checking it other than with a new
charged battery. However, if you have access to any, you could temporarily connect a couple of car batteries in
series to give the 24 volts and ensure it's basically running ok.
.

 

[projem]

Testing motor with less volts?

Would it be possible to use one 12 volt battery, just to see if it spins, could this damage the motor using less volts? Thanks

 

[flecc]

You couldn't damage anything, but it may not get the motor turning. However, if you get the motor buzzing, a
hand spin may get the wheel turning, indicating the motor is ok.
.

 

[projem]

Injecting 24v

You couldn't damage anything, but it may not get the motor turning. However, if you get the motor buzzing, a
hand spin may get the wheel turning, indicating the motor is ok.
.

Thanks flecc, didnt want to buy a battery pack and charger only to find the motor defunct.... should a low mileage motor, left in a dry environment, deteriate over 10 years? There seems alot of belts spinning etc . Anything I should do/grease/clean before injecting 24v after such a time?
Thanks

 

[flecc]

No, there shouldn't be any deterioration, it isn't necessary to do any preparatory work to check it out, especially as it's had low usage.
.

 

[projem]

Charger to battery box connector

Perhaps the forum experts could cast an eye on this charger

Thanks flecc regarding motor maintenance..

I need to get the other end of this connector to glue within the battery box, can anyone tell what there called as "3 pin standard connector" brings up many when Googled.

Can anyone recommend better connectors for both ends that may be suited to a flush battery box surface with waterproofing in mind, thanks.

 

[flecc]

That connector is a microphone one that's sometimes been called an NTC connector in the past. Common in
China but more rarely used here.

Best replaced with the more easily available fractionally larger XLR connectors. If you look on the Maplin page
below you'll see an XLR plug and XLR chassis socket which are ideal, both 3 pin. The convention is to wire one
thermistor active lead to the centre pin, the other going with negative to either side pin:

XLR connectors at Maplins, online or via their stores

N.B. Two socket types if you scroll down, one with a circular locking ring, one with a two small bolt plate which
is more commonly used on bike batteries
.

 

[NeilP]

Reviving an old thread here..I have just acquired one of these too. Was given with a new merc, but it beats the 'twice around Hyde park usage..this one was never even charged once or used at all.

Would expect the battery to be totally dead, have put it in on charge ..you never know. I had heard that rechargeable cells are often manufactured with some sort of 'stabiliser' in the chemistry, and the cells do not become 'active' till after the first charge. Never researched this or even bothered about it before..so if this battery has really never been used...unlikely but interesting to see.

Have seen 12 Ah LiFePO4 packs now available for it..so that will be the option. Not keeping it myself..so it will be up to who ever purchases it off me..i'll do the work, they'll pay

 

[RobF]

A pic or two of the bike would be nice, Neil.

 

[NeilP]

Well exactly the same as the pics on the first page fo the thread..but here you go

 

[RobF]

Well exactly the same as the pics on the first page fo the thread..but here you go

View attachment 6258

View attachment 6259

Ah, but yours is nice and shiny and new.

Like the butterfly bars.

 

[NeilP]

True..tyres are past it..perished..as is the foam on the bars.

Going to put old tyres on for now and leave bar grips..till I get a battery rigged up..even a temp one for now, just to see how it goes. Demo it to potential purchasers, before ordering a £350 battery pack for it..Unless TETS can do me a better deal