Lion batteries in series and parallel

I'm very unfamiliar with lion batteryes, so don't laugh for those questions
Can I connect lion bateries in series and parallel like other types of batteries (nimh, nicd...)without any precautions? I saw that some lion batteries have some kind of protecion in it, should I buy batteries with or without it?
I want to make two batteries in series x2 and put those two pairs in parallel, I think I will got 7.2V 2.5Ah in that way? I will put that somehow in my bike bottle (bidon) and charge it somehow. Is there any advice how to do that?

Sponge said:

I'm very unfamiliar with lion batteryes, so don't laugh for those questions
Can I connect lion bateries in series and parallel like other types of batteries (nimh, nicd...)without any precautions? I saw that some lion batteries have some kind of protecion in it, should I buy batteries with or without it?
I want to make two batteries in series x2 and put those two pairs in parallel, I think I will got 7.2V 2.5Ah in that way? I will put that somehow in my bike bottle (bidon) and charge it somehow. Is there any advice how to do that?

Click to expand...

Here you go !
https://www.candlepowerforums.com/threads/206716


Robert M.

I think I will got 7.2V 2.5Ah in that way?

Click to expand...

You did not type what batts to use, but: NO

You put 2 in series --> voltage doubles,
You put 2 in parallel --> capacity doubles

as the common Li-Ion cells have
AA --> 800 mAh
CR123 --> 600-800 mAh
18650 --> 2200 mAh
there is no way You could end up with 2.5 Ah

Sabrewolf said:

Here you go !
https://www.candlepowerforums.com/threads/206716


Robert M.

Click to expand...

thanks, Robert!
is this setup right:
first connect two batt. is parallel (two times), than connect those two pairs in series. than connect it to PCB with balancing function...and that's it. No protection in batteries needed?
But how to charge this pack?

yellow said:

You did not type what batts to use, but: NO

You put 2 in series --> voltage doubles,
You put 2 in parallel --> capacity doubles

as the common Li-Ion cells have
AA --> 800 mAh
CR123 --> 600-800 mAh
18650 --> 2200 mAh
there is no way You could end up with 2.5 Ah

Click to expand...

I will use total 4 batteries 18650, two in series x2, than those two pairs in parallel

Sabrewolf said:

Here you go !
https://www.candlepowerforums.com/threads/206716


Robert M.

Click to expand...

where to buy those protection PCB? I live in Croatia, Europe

You could use these: http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=1083

but You could also get Canon BP945 Camcorder packs and charge them with Your Camcorder
(they have the protection built in)

yellow said:

You could use these: http://www.batteryspace.com/index.asp?PageAction=VIEWPROD&ProdID=1083

but You could also get Canon BP945 Camcorder packs and charge them with Your Camcorder
(they have the protection built in)

Click to expand...

can I use protected batteries like this:
http://www.dealextreme.com/details.dx/sku.5790
and charge it (every time unpack the pack) in something like this:
http://www.dealextreme.com/details.dx/sku.13820

can I just put them in series an parallel like nimh batteries?

Just buy a battery from here.
http://www.all-battery.com/74vli-ionbatterypacksandmodules.aspx
No need to make your own pack.

Some people have reported camcorder batteries not allowing enough current before tripping the protection.

You can make your own. But I'm guessing for your case it's better to just buy the pack and charger, its dirt cheap anyways.

Since it seems your new to Li-ion chemistry,reading up on the dangers/benefits would be a great place to start.
Li-Ion Protection Technology
Greatest Danger Using Li-Ion

The configuration your asking for is 2S2P(two serial/two parallel).LITEmania has a pack already made up here,Kentro P7 Bicycle Headlamp.He also has a charger available in the same thread.

You can see more pics on his site,litemania.com

The price is reasonable.By the time you figure the cost of shipping for batteries,protection circuits,connectors,chargers etc.,if you build one yourself,you probably couldn't put one together for that.And you can familiarize yourself with the chemistry safely,then you will be armed with knowledge to DIY later.

-Michael

TexLite said:

Since it seems your new to Li-ion chemistry,reading up on the dangers/benefits would be a great place to start.
Li-Ion Protection Technology
Greatest Danger Using Li-Ion

The configuration your asking for is 2S2P(two serial/two parallel).LITEmania has a pack already made up here,Kentro P7 Bicycle Headlamp.He also has a charger available in the same thread.

You can see more pics on his site,litemania.com

The price is reasonable.By the time you figure the cost of shipping for batteries,protection circuits,connectors,chargers etc.,if you build one yourself,you probably couldn't put one together for that.And you can familiarize yourself with the chemistry safely,then you will be armed with knowledge to DIY later.

-Michael

Click to expand...

I have read all articles on CPF, and conclusion is that safest way to charge batteries is to charge every cell individualy and than connect it and make a pack. Batteries should be with protection. Charger must supply 0.5 or 1C to fiil battery properly, and has to shutdown after charge is done. Not to trickle charge cell, since that can lead to fire&explosion.

Did I miss something

Sponge said:

I'm very unfamiliar with lion batteryes...

Click to expand...

Thats the reason I made the recommendation to read up.

Sponge said:

I have read all articles on CPF, and conclusion is that safest way to charge batteries is to charge every cell individualy and than connect it and make a pack. Batteries should be with protection. Charger must supply 0.5 or 1C to fiil battery properly, and has to shutdown after charge is done. Not to trickle charge cell, since that can lead to fire&explosion.

Did I miss something

Click to expand...

Another important precaution is to avoid discharge currents above 2C.

The reason I suggested to buy the pack litemania has listed,is its cheaper than even the premade pack linked to above,and he has a charger available.He also ships internationally for $5.00.Its a finished pack complete with wiring,case,and an attachment strap.

By the time you add up the shipping,if you have to purchase components from multiple vendors,the cost can quickly escalate past the price you could purchase a completed pack for,especially when some dealers charge huge international rates.

-Michael