A question about A123 battery chargers

[mightymouse]

I have just bought a 4s pack A123 batteries and a b8080 novatech charger, from BRC hobbies.

In the blurb on the website it said that the standard battery pack will not connect to the charger without an adaptor lead so I bought on of these as well. Ok up to now.

The Battery lead does plug into the socket on the charger and so does the adaptor, but the adaptor will not fit the battery pack. But most disconcerting is that the positive and negative leads on the adaptor and batt pack are completely opposite. ???

Help - anybody??

Trev

[leorcc]

A question about A123 battery chargers

Have you got some links and pictures of them Trev?

[leorcc]

A question about A123 battery chargers

Trev, Unless I have missed an update on these chargers, the B8080 is a LiPo charger, not a LiFePo4. Can you check that your charger is suited for A123s?

[mightymouse]

A question about A123 battery chargers

Leo, charger is Li/ion and Li/poly

Had the wrong adaptor cable, all connects now, but I have yet to use it.

It is very hard to get good information for these things - I bought it so that I could vote at the next FRA meeting with some experience - but so far I am more confused. I bought a 4.8v regulator to power the reciever from the batt pack and the sheet of paper that came with it said soldering required, but no circuit diagram and it doesnt even say which is the input or ouput. I can figure it out but many will struggle. It really is not good enough when these batteries, if abused, can go wrong bigtime.

Gripe over

Trev

[woody]

A question about A123 battery chargers

Heres some info Trevor on the A123 bats just incase....

Theyre NOT Li/ion or Li/poly theyre
Li-Ion FEPO4 nominal voltage 3.3v.

Specs and charging recommendations etc here ....
http://www.first-products.de/specsenglisch.htmhttp://www.first-products.de/specsenglisch.htm

[mightymouse]

A question about A123 battery chargers

Woody, are you saying this charger is no good?

Trev

[woody]

A question about A123 battery chargers

Not a clue .... Id need to turn the question around and ask you ...do the charger specs include A123 Batteries?

Chargers usually list A123 bats if theyre suitable for charging them.
Otherwise you need a Lipodapter or similar ....http://www.slkelectronics.com/lipodapter/index.htmhttp://www.slkelectronics.com/lipodapter/index.htm

(Message edited by woody on December 22, 2007)

[geeza]

A question about A123 battery chargers

From what Ive just read, doing a quick search, then the voltage cut off is at 4.2V. But wether that means its too high for charging M1s, I dont know. I also read that this charger did orginally overcharge batteries, but was updated with a lower cut off.

[mightymouse]

A question about A123 battery chargers

The battery packs are listed as BRCfePo4 but then refer to them as lithium-ion

http://www.brchobbies.co.uk/product_images/20070712105906_FEP04%20016.jpghttp://www.brchobbies.co.uk/product_...EP04%20016.jpg

Can someone please enlighten me before I blow up a £65 battery pack.

[woody]

A question about A123 battery chargers

http://www.first-products.de/product8.htmhttp://www.first-products.de/product8.htm

From the same site that I previously linked to ...looks exceedingly similar ...possibly rebadged.

Id suggest the additional purchase of a lipodapter.

(Message edited by woody on December 22, 2007)

[mightymouse]

A question about A123 battery chargers

It does. I think a call to BRChobbies is necessary, if the charger is not suitable I will exchange it.

Thanks for your time lads and I will update this link when I have contacted them, hopefully, they will be working tomorrow.

Trev

[leorcc]

A question about A123 battery chargers

Also, check out the lithium thread in the safety section of the forum, there is now quite a large selection of chargers and balancers for A123. And since these batteries are becoming more and more commonplace, the list keeps growing and growing.

http://www.fightingrobots.co.uk/discus/messages/9/8008.html?1198073230http://www.fightingrobots.co.uk/disc...tml?1198073230

[mightymouse]

A question about A123 battery chargers

Been in touch with BRChobbies and they confirm that the novatech b8080 charger is compatible.

The label Li-ion covers A123 batteries as they are Li-ion type.

Trev

[leorcc]

A question about A123 battery chargers

Im sorry but that is not true! The voltage cut-offs are way different. They are absolutley wrong!

[leorcc]

A question about A123 battery chargers

quote:

A123s are designed to be charged to 3.6v per cell. Lipo chargers charge to 4.2 so they must not be used (directly) with these cells. Dont be misled by the fact that your lipo charger is designed for 3.6 or 3.7v lithiums (learn the difference between nominal and charge voltages). Your options for charging (from 12v) are as follows:

1) Upgrade or buy a new charger that can do A123s
2) Make or buy a Dapter - this allows you to use a nicad or lipo charger with A123 packs (it regulates the voltage correctly)
3) Make a cheap and very effective charger yourself...

A123 cells have a 3.3V nominal voltage, instead of the 3.6V and 3.7V for Li-Ion or LiPo. Should you put 4.2V into your A123 cells they will go bad. They will not explode but they will deteriate quickly.