DIY Scurion Batteries

Just found this...

http://souterweb.free.fr/boitaoutils/eclairage/annexes/Fabrication%20personnelle%20de%20batteries%20compatibles%20Scurion.pdf

Even with my limited (read:non-existent) French, it looks fairly straight forward.

Has anyone tried? Or does anyone with better French than I read the conclusion as 'this is a silly idea, don't do it'?

Thoughts?

Its a standard setup. You can get the battery management PCBs from FastTeck. The board the writer refers to a turning off the cells was a faulty unit, I hit one once. But the "square" PCBs are better as they will give a slow death rather than an abrupt switch off. When assembled the PCBs will be in an off state anyway until connected to a charger. This is because they are used in laptops and phones etc and will be in the off state for safe shipping. You will have all bought something like that and believed the battery to be flat. It isn't, its just electronically disconnected until connected to a charger.

The writer also appears to be using high capacity 3400 mAh cells which are actually better than the standard battery packs (2600 mAh cells) which are an off the shelf item that uses lower capacity cells, now its 3500 mAh.

Only issue with doing this, apart from knowing how to use a soldering iron etc, is the lamps. If the manual warns to only use their batteries, its wise to do so, if it says OK for other battery types subject to voltage, it would be OK to make up the DIY power packs.

Above is what I originally wrote, now I am editing it.
If he is using 18650 battery holders rather than soldering to the cells, forget it!
The PCB disconnect was due to a knock causing a temporary circuit break to the PCB, this will cause a switch off until connected to a charger.
We all know about knocks and bangs underground don't we.

Unless you feel competent to solder direct to the cells, and it does not destroy them, several large manufacturers are doing this. forget the idea.

royfellows said:

If he is using 18650 battery holders rather than soldering to the cells, forget it!

Click to expand...

Interesting you should say that. A few years ago I switched to loose cells in a (custom) 18650 holder for my light and I've found it to be a much better solution than using a soldered battery pack. Much easier to see any physical damage to the cells because they're not hidden under shrinkwrap, much easier to identify cell capacity issues early because they are individually charged, and quicker/cheaper to replace when required.

MarkS said:

royfellows said:

If he is using 18650 battery holders rather than soldering to the cells, forget it!

Click to expand...

Interesting you should say that. A few years ago I switched to loose cells in a (custom) 18650 holder for my light and I've found it to be a much better solution than using a soldered battery pack. Much easier to see any physical damage to the cells because they're not hidden under shrinkwrap, much easier to identify cell capacity issues early because they are individually charged, and quicker/cheaper to replace when required.

Click to expand...

If you have dumped the battery management circuits you obviously wont have the issue I describe, and if you are using cells with their own individual protection circuits you have found a workable solution. My comments related to what was described in the article being referred to.
Nothing wrong with using removable cells, but I would not recommend changing them underground.

Obvious issue is coming up with a protective case that has good waterproof integrity and impact resistance without being as big and heavy as a brick. If you have done this I would say that there people in here that would like to hear about it.

royfellows said:

MarkS said:

royfellows said:

If he is using 18650 battery holders rather than soldering to the cells, forget it!

Click to expand...

Interesting you should say that. A few years ago I switched to loose cells in a (custom) 18650 holder for my light and I've found it to be a much better solution than using a soldered battery pack. Much easier to see any physical damage to the cells because they're not hidden under shrinkwrap, much easier to identify cell capacity issues early because they are individually charged, and quicker/cheaper to replace when required.

Click to expand...

If you have dumped the battery management circuits you obviously wont have the issue I describe, and if you are using cells with their own individual protection circuits you have found a workable solution. My comments related to what was described in the article being referred to.
Nothing wrong with using removable cells, but I would not recommend changing them underground.

Obvious issue is coming up with a protective case that has good waterproof integrity and impact resistance without being as big and heavy as a brick. If you have done this I would say that there people in here that would like to hear about it.

Click to expand...

Ah, OK I see what you mean. The case I use is just an old Rude Nora 3 x 18650 battery box. I made a couple of little inserts which give virtually no room for the batteries to move at all.

Sounds OK.
A lot of useful stuff for DIY lamp building on sale here from a good shop
http://customduo.co.uk/Bazaar/

But caution. I believe that Rude Nora is low voltage (3.7V nominal) while Scurion is higher (7.4V nominal).

royfellows said:

But caution. I believe that Rude Nora is low voltage (3.7V nominal) while Scurion is higher (7.4V nominal).

Click to expand...

Don't worry - it's for a home made lamp rather than a Nora!