Yamaha Easy - Battery re-cell

[halfmedley]

Has anyone tried to re-cell the 24v NiMH battery for a Yamaha Easy? The range on my Easy has deteriorated recently, and given the bikes age I suspect the cells have had it.

There are a number of suppliers in Germany who can supply the internal cells in the correct and balanced arrangement, like these for around £200:




But obviously you've still got to fit it. And this is my question - has anyone tried?. I haven't undone the case yet to set what wiring/soldering difficulties await so I would appreciate any advice. Thanks.

 

[Fordulike]

Why not drop BGA-reworking (aka INSAT International) a line, and see if they can refill your pack.

They might be able to fill it with new lithium-ion batteries instead, for a similar price to the German supplier.

 

[halfmedley]

Yes, that could be an option. I'd thought about Lithium batteries to save some weight. The downside would be I'd need a new charger too, I don't think the NiMH charger would work. Also the NiMH charger has a proprietary Yamaha plug which goes into the battery casing socket, and I doubt that would be matched on a new Lithium charger, so then I'd have to alter the casing too.

I think I'm going to attempt to open the battery case over the bank holiday to see what's what. Does anyone know of any electrical hazards I should be aware of?

 

[flecc]

There's no specific hazards so long as you don't disconnect wires and short them together.

To replace the cellpack you need to swap just two connections, the positive and negative ones onto the cellpack ends, don't disconnect anything else.

There is other wiring inside, those wires that connect to an NTC thermistor and those that incorporate a fuse or fuses, but you don't alter those. If the battery has an LED meter that will have wires too, also not needing to be altered.

The thermistor is a small bead like device with two wires, attached to or inserted in the cellpack, so all you do with that is put it into the identical position in or on the new cellpack, without disturbing its connections.

So once you have the case opened, note where everything is and how the wires are laid. Then you'll be able to imitate that when fitting the new pack, only needing to solder the two connections onto the new pack's ends.
.

 

[halfmedley]

The case was easy (excuse the pun) to open - undo four screws, slide out the mounting plate and squeeze the case sides together to release the inner plastic lugs. This was revealed at the discharging end (connects to the bike):



And this was revealed at the charging end (connects to the mains charger):



I couldn't see how the wires connected to the cells as they were covered with shrink wrap complete with severe warning label. I was surprised by the number of wires and the 2 amp fuse! I didn't go any further as I didn't want to damage anything. I think I need an electrical engineer for this job.

 

[Kuorider]

Call Jimmy at Insat for advice. He can re-cell the battery and supply the correct charger & plugs .Really helpful guy & quick service .

 

[flecc]

The case was easy (excuse the pun) to open - undo four screws, slide out the mounting plate and squeeze the case sides together to release the inner plastic lugs. This was revealed at the discharging end (connects to the bike):

View attachment 15258

And this was revealed at the charging end (connects to the mains charger):

View attachment 15259

I couldn't see how the wires connected to the cells as they were covered with shrink wrap complete with severe warning label. I was surprised by the number of wires and the 2 amp fuse! I didn't go any further as I didn't want to damage anything. I think I need an electrical engineer for this job.

As said, you don't need to disturb or change any of the wiring, but you would need to open the shrink wrap enough to get at where the two wires are joined onto the cellpack. That's what gets swapped, just the cellpack, the two wires rejoined onto the new one and the thermistor reinserted to where it was before.

We used to do this with the popular Giant Lafree and I have an instruction web page for that which you can look at. You'll see that has lots of wires too, but how only the cell pack gets changed. The last paragraph states for other makes what I've posted here.

Here's the link.
.

 

[halfmedley]

Update:

Thanks to a chance conversation with the owner of Sandwell Cycles (seller of Volt electric bikes) and my own hesitation in re-celling the Easy battery myself, I was put onto a company in Walsall called Sertronics Limited.

I don't know if they've been mentioned on this forum before, but after visiting Sertronics on December 22nd I decided to give them the work as they do this sort of thing for a living.

I received the battery back (delivered by the engineer no less) on January 6th, which, allowing for the Christmas/New Year break, is pretty good service.

So what did I get? Well, a substantial upgrade from the original 24v 9AH NiMH original to a 24v 12AH Lithium Ion. Which, happily, has reduced the weight of the battery from a little over 4kg to just under 2kg. I'm hoping for a noticeable handling and performance (range) improvement. I also got a new charger, onto which the engineer had fitted the connector from the old charger so that the battery case didn't have to be modified in any way. The old charger was returned too, and they disposed of the NiMH batteries. All of which came to about £300 including VAT and a 12 month guarantee to boot.

Personally I think that's pretty good considering a new like for like NiMH replacement from Germany was hitting £200 without any fitting. Of course the proof of the pudding will be in the eating and I will report again later in the year after thorough road testing.

Battery re-celler info:

West Midlands - Sertronics Ltd, WS2 9HQ

Others (not used, but might be useful to people not in the West Mids)

East Midlands - Multicell (Leicester)
The South - InSat (as mentioned in this thread)

Happy New Year!

 

[simony]

Update:

Thanks to a chance conversation with the owner of Sandwell Cycles (seller of Volt electric bikes) and my own hesitation in re-celling the Easy battery myself, I was put onto a company in Walsall called Sertronics Limited.

I don't know if they've been mentioned on this forum before, but after visiting Sertronics on December 22nd I decided to give them the work as they do this sort of thing for a living.

I received the battery back (delivered by the engineer no less) on January 6th, which, allowing for the Christmas/New Year break, is pretty good service.

So what did I get? Well, a substantial upgrade from the original 24v 9AH NiMH original to a 24v 12AH Lithium Ion. Which, happily, has reduced the weight of the battery from a little over 4kg to just under 2kg. I'm hoping for a noticeable handling and performance (range) improvement. I also got a new charger, onto which the engineer had fitted the connector from the old charger so that the battery case didn't have to be modified in any way. The old charger was returned too, and they disposed of the NiMH batteries. All of which came to about £300 including VAT and a 12 month guarantee to boot.

Personally I think that's pretty good considering a new like for like NiMH replacement from Germany was hitting £200 without any fitting. Of course the proof of the pudding will be in the eating and I will report again later in the year after thorough road testing.

Battery re-celler info:

West Midlands - Sertronics Ltd, WS2 9HQ

Others (not used, but might be useful to people not in the West Mids)

East Midlands - Multicell (Leicester)
The South - InSat (as mentioned in this thread)

Happy New Year!

How did the bike worked after the recell job?
Simon