Need some advice recovering some batteries

[El Champiero]

As for battery tab welders I am going to build this one: http://frikkieg.blogspot.co.uk/

It looks like the best one around for giving consistently good welds and you can buy the PCBs and all the instructions too.

An SCR fired one will work but I want to build one which is close to or in fact better than commercially available ones which can weld 0.15mm or 0.2mm thick nickel.

 

[pdarnett]

That's some heavy duty stuff, looks good though and very well laid out.

 

[El Champiero]

It certainly is. One challenge will be actually getting all the components. I think a combination of eBay, aliexpress, Farnell and maybe Maplins will be used. Also, several visits to our electrical waste holding area at the hospital I work at might well be in order to grab stuff for cabling and also perhaps a project case to contain it all.

With commercial welders costing about £1000 upwards I think I can build this one for about half the price or maybe cheaper (with my time not costed)

 

[pdarnett]

I have a WEEE cage as well at my NHS Trust, that's where the laptop batteries I have may ..erm come from.

 

[El Champiero]

Ah, the perks of the job! Me being the waste manager has its benefits!

 

[El Champiero]

From what I have read, a microprocessor CD welder will always be much more consistent compared with a standard SCR fired one. It will take a long time to build this but I am sure to learn a heck of a lot more about electronics in the process!

 

[pdarnett]

Nearly finished the bike now. Had a test spin today, very smooth ride and the PAS is excellent. Used the recovered battery (after making a mount for it) and all good. Just need a right angled plug for the power as it's too close to the front derailleur. Just need some fine weather to start using it for work.

 

[El Champiero]

Looks good - I like the frame mount system for the battery

 

[pdarnett]

The mount is just two bars of tubular aluminium with two thin plates across it (like a ladder) that slots into the powabyke mounts (see earlier) and then i've got a pin that slides in to stop it sliding up out of the slots.

The tiny bag was a mistake (for the controller) gets a bit too hot in there. Trying a triangle bag but really don't like the look of it on the bike.

 

[jackhandy]

The mount is just two bars of tubular aluminium with two thin plates across it (like a ladder) that slots into the powabyke mounts (see earlier) and then i've got a pin that slides in to stop it sliding up out of the slots.

Diversifying a bit - Did you work out how the original battery locked into those mounts, to prevent burglary?
I couldn't suss it & ended up taking the battery off when the missus left the bike anywhere.

 

[pdarnett]

I have a pin that goes through between the two mounts to stop the battery being slid up. With a padlock through the end of the pin (or round bar) on the new mount. With the original battery I'm probably going to fashion a metal loop attached to the top plate that a cable lock can go through.

 

[pdarnett]

Well did 10 miles on the recovered battery (start of thread), starting voltage 41.8, end voltage was 40.6 so not bad really. Pedal assist on all the time and a bit of moderate work from me, but not too shabby. Proving it can be worth while to recover a "dead: battery if you've got the patience. Now waiting for my replacement cell for the other one to work my magic on!

 

[pdarnett]

Don't bother with Hobbyking, they billed me twice, it took 7 emails and 3 live chats to deal with the refund, then they didn't action it. Had to get paypal to intervene. Then three weeks later still not batteries, another 5 emails and 4 more live chats and no movement. I've had to get paypal involved again as HK won't refund me again. So back to hunting elsewhere for these packs.