Charging A123s on EOS0606i

[Webbage]

Hi, ya'll

I got my A123 packs last week, and my Hyperion charger. Both rock bells, but I have quandary. The 606i defaults to charging the packs at 1C. In my 1100mAh packs that's about 1.1A. That'd be grand for a LiPo, but for A123 it's a bit wimpy. I don't understand, form Hyperion's manual, how to make it charge at a higher current and still stop at the right time and not end up sending my new A123 pack into orbit According to the manual the 606i can charge at 50W max, so 5.05A. I think A123s will take a lot more than that so amperage wise it'll be safe enough, I just don't want to fry the packs.

Anyone know the answer?

 

[CharliesTheMan]

You need to set the charger for the kind of battery that you're charging, and the size of the battery and cell count, and it will take care of the rest. I think you're trying to use the default nimh setting or something apparently.

There's some instructions that come in the box with the charger and they'll tell you exactly what to do for every kind of battery.

It will charge up to six amps. It will peak charge the pack, which is what you want. You want it to cut off when the pack is fully charged, rather than charging by a preset time. Don't freak out when it goes passed the advertised mah. My 6000 mah LiPo packs peak at about 6400 mah, and the 2000 mah packs peak at about 2200 mah I believe.

 

[sweetdiesel]

You can just double the capacity rating on the Hyperion for your battery to force it into charging at 2C.

For example, if your A123 pack can be safely charged at 2C, and you have a 1100mah pack....set the charger to pack capacity of 2200 mah and the Hyperion will automatically charge at 2.2 amps.

 

[CharliesTheMan]

And for future reference, whatever sweetdiesel says about charging batteries, you can consider it law and write it in stone. He knows his electrics, better than almost everyone that I know.

 

[Webbage]

You need to set the charger for the kind of battery that you're charging, and the size of the battery and cell count, and it will take care of the rest. I think you're trying to use the default nimh setting or something apparently.

There's some instructions that come in the box with the charger and they'll tell you exactly what to do for every kind of battery.

I worked that bit out for myself, but thanks : Bless you, I know you're only trying to help FWIW I think it'd have sworn at me if I'd tried to charge a LiFe on the NiMH setting!

Oh and mine came with a cute note telling me to download the manual off the website, apparently they didn't include a paper copy because of 'time restrictions'.

Either way I read the manual at least twice before it even turned up anyway, so I knew pretty well what I was doing, but followed the words again just in case. I plugged the balancer in and everything, and it found it

I tried flicking through all the menus with it set to 'LiFe' mode, but there's nothing that lets you set the charge amperage. Like you said, you put the battery details in and it decides itself what to do.

It will charge up to six amps. It will peak charge the pack, which is what you want. You want it to cut off when the pack is fully charged, rather than charging by a preset time.

It'll charge at 6Amps *if* it doesn't exceed 50W. It'll manage 7.2V at 6Amps easy, and 8.4V at just shy of 6Amps but when you get into 3-cell A123s at 9.9V it'll only stagger up to about 5.05Amps.

Remember P = V x I - 9.9 x 5.05 = 50W.

If you use NiMH or NiCad it *will* let you set it to a higher amperage, but with A123 (and probably LiPo) it makes it's own mind up. That's fine for LiPo because charging at 1C is the only safe way, but it kinda sucks for A123, seeing as how the whole point is that it charges at high C.

It uses peak charging, and seems to work pretty well. As far as I can see it doesn't do timed charging. I might have missed that bit in the PDF tho.

Don't freak out when it goes passed the advertised mah. My 6000 mah LiPo packs peak at about 6400 mah, and the 2000 mah packs peak at about 2200 mah I believe.

Yeh my stick packs should take 30 mins from flat at 3Amps and are only 1500 mAh and went up to about 1780mAh and 32mins. As my dad pointed out though that's what the charger pushes *out* though, the battery pack drops some of it as heat and lack of efficiency.

You can just double the capacity rating on the Hyperion for your battery to force it into charging at 2C.

For example, if your A123 pack can be safely charged at 2C, and you have a 1100mah pack....set the charger to pack capacity of 2200 mah and the Hyperion will automatically charge at 2.2 amps.

AhHA! I thought this might be the way around it. Because it uses peak charging then it stops as soon as the battery reaches full charge, regardless of what mAh you tell it, right?

And for future reference, whatever sweetdiesel says about charging batteries, you can consider it law and write it in stone. He knows his electrics, better than almost everyone that I know.

Duly noted...

 

[sweetdiesel]

AhHA! I thought this might be the way around it. Because it uses peak charging then it stops as soon as the battery reaches full charge, regardless of what mAh you tell it, right?

It uses CC/CV charging, which slowly increases the current to the battery up to the maximum amp rate. Once the pack reaches the maximum voltage for your particular pack, it switches to a constant voltage charge algorithm and decreases the current. Your packs should never get overcharged or undercharged.

 

[Webbage]

It uses CC/CV charging, which slowly increases the current to the battery up to the maximum amp rate. Once the pack reaches the maximum voltage for your particular pack, it switches to a constant voltage charge algorithm and decreases the current. Your packs should never get overcharged or undercharged.

Right, I hit up Mike at CBP and asked him for a max charge figure and he says A123s can take up to 4C. That means my pack will take up to 4.4 Amps.

So that means if I set it to 4000 mAh it'll be comfortably inside that, right?

 

[sweetdiesel]

You can set it at 4400 mah for a 1100 mah pack, so yes 4000 mah will be comfortably below the maximum charge rate.

 

[CharliesTheMan]

I've got some A123s on the way to test for a big company and I'm really looking forward to trying them out. I'm really hoping they aren't too heavy because I like the idea of such high charge rates.

 

[Webbage]

You can set it at 4400 mah for a 1100 mah pack, so yes 4000 mah will be comfortably below the maximum charge rate.

Thanks mate :thumbup:

I've got some A123s on the way to test for a big company and I'm really looking forward to trying them out. I'm really hoping they aren't too heavy because I like the idea of such high charge rates.

Don't expect them to be as light as LiPo. You'll be disappointed. They are many worlds lighter than stick or saddle packs though. There's a bit of weight in my 3Ss but not so much that they feel unsuitably heavy for a crawler. Quoted weight is 4.59oz.