Lithium cell tests

[woody]

Some info here:-
http://www.fmadirect.com/support_docs/item_1229.pdfhttp://www.fmadirect.com/support_docs/item_1229.pdf

[dragonmaster_1]

Hi John
Been trying to get in touch dont know if you got my emails. If not could you email me reference what we talked about at the EU champs
Regards Tony.

[terrorhurtz]

Sent an email Tony.

Yes, the ones in the DeWalts are the ANR26650 cells (26mm diameter, 65mm long). These are the only cells that A123 currently produce. The larger cells (M1 HD and M1 Ultra) are not in production yet.

The A123 cells do seem to perform slightly better when warm, but apparently they still suffer a reduction in life if they go over 60 deg C.

The main reason to balance the cells is so that we can use simple chargers at competitions - so we dont have to fiddle around connecting all the balance wires every time they need to be charged. Also cheaper.

[woody]

Commercial chargers are now availiable but the associated multicell balancing is not
http://www.astroflight.com/store/store-type-tem.html?item=products:af-106-123&sid=0001jLBTKVBTuxwtQ82c916http://www.astroflight.com/store/sto...:af-106-123&si d=0001jLBTKVBTuxwtQ82c916

[woody]

This German manufacturer can supply A123 gear ... at a price ...the charger is expensive but it has a great range.
http://www.first-products.de/pulsarbeschbgengl.htmhttp://www.first-products.de/pulsarbeschbgengl.htm

Cheap six cell balancer .... can these be Daisy chained?

http://www.astroflight.com/store/store-type-tem.html?item=products:af-106-123&sid=0001jLBTKVBTuxwtQ82c916http://www.astroflight.com/store/sto...VBTuxwtQ82c916

(Message edited by woody on August 09, 2007)

[leorcc]

Schulze in Germany has also confirmed that next to its line of chameleon chargers their LipoProfiBal8 and 14 is also suited for balancing A123 systems cells.

[terrorhurtz]

Woody - I think what Andy meant is that there is no 10 cell balancer currently available. It is anticipated that most heavyweight robots will use 10 cell packs. The Astroflight only does up to 6 cells.

[leorcc]

Schulzes biggest one up to 14 (see other topic).

[bugs]

Can we keep the techincal discussion on Li-technology for another topic?
The problem I have at the moment is that I work with lithium batteries on a professional level, and therefore have a good understanding of the possibilities and risk involved. Yet even though the A123 cells seem safe enough (not more dangerous than NiMh) and I am perfectly capable of handeling the cell balancing problems, Im not allowed to use this technology.
This is frustrating, especially since I have to wait until other teams have demonstrated its safety, and effectively have quite a sizable advantage over the rest. This is assuming they are not obliged to couteract the weight advantage.
Why not provisionally allow the use of A123 cells, with an obligatory through techcheck to make sure it is used correctly?

[andy_kane]

Stefan,
While you may be quite capable of handling A123 cells safely there will be be quite a few teams that cannot as yet.

Could you mail useing info@fightingrobots.co.uk with what info you have please. It would then be put around the test group.

On A123 subjects can we transfer to the thread on safety discussions please?