My PILA charger mod (with a couple pics)

[737mech]

I know this looks crazy but it's really convenient for me to charge all the different cell sizes I use. I have most of the common sizes covered 18650, 18500, 16340, 26500 and the KD D cell. I opened up the charger and soldered some teflon coated 22 guage wire to the backside of the positive terminals and then routed the wire through a couple holes I drilled in the back of the charger. I drilled two more holes for some screws, washers, and nuts for the positive "post" to clip my wires to. Crimped a couple connectors on the ends of the 22 guage wire and fastened them to my posts. I bent some sheet metal up and painted it black. Then I used pop rivets to install a few battery cradles I made up (with 18 guage silicone wire, heatshrink and clips) to the metal. Secured the charger with some velcro and presto, my own custom made charging station. Of course I can only do two cells at a time but it makes charging different cell types a breeze. I was using a couple screws in the holes on the positive side of the charger for a while but came up with this idea instead.

(I know a couple of the cradle's look crooked and uneven but they aren't I swear!)

 

[NutSAK]

It looks like a good setup to me--not too crazy. :thumbsup: It's not much different than the setups many of us use with our hobby chargers, and you have the benefit of having two channels working at a time.

 

[hazna]

Everyone run! His got a bomb!

 

[fishinfool]

Everyone run! His got a bomb!

:lolsign:

 

[VidPro]

how did you make your own battery cradles?

 

[737mech]

how did you make your own battery cradles?

I didn't actually "make" the cradles. More like put them together.They are Bulgin cradles. I just had to modify them a bit to mount them on the sheet metal. I also had to solder the wires/clips and install the heatshrink. But judging by your post count I sense you might know this and that you might be flaming me a bit

 

[Pekka]

Is it... safe?

 

[VidPro]

I didn't actually "make" the cradles. More like put them together.They are Bulgin cradles. I just had to modify them a bit to mount them on the sheet metal. I also had to solder the wires/clips and install the heatshrink. But judging by your post count I sense you might know this and that you might be flaming me a bit

no, they arent pretty, but they look much more substantial than the vinyl plastic junk from the radio shack. and for some of the packs i do the Metal ones dont help anything, because of putting them together in stuff like belt packs. having metal chunks and strips with stacked holders, just doesnt work.
you dont happen to have a link to where you got the bulgin ones?

With the RS ones , i have to completly re-do everything on them, and by the time i get done the plastic is melting and they are a total pain.

 

[737mech]

got em from mouser.com . I was using the Radio Shack cheapies and saw these on another thread. They are WAY better (IMO) and more substantial for sure.

 

[737mech]

Is it... safe?

I HOPE SO!


but no seriously its safe. All the wires and stuff make it look kinda crazy. Like a previous poster mentioned, setups similiar to this with hobby chargers is pretty common.

 

[VidPro]

got em from mouser.com . I was using the Radio Shack cheapies and saw these on another thread. They are WAY better (IMO) and more substantial for sure.

thanks, does a 4xD exist ? or a 8xD ? darn, i set the search filter and it says "change it or you get Nothing " figures.

 

[mdocod]

Neat setup!

You can actually charge more than 2 cells at once if you wanted to, just wire them up in parallel and treat them as a single cell. Ideally the cells to be charged together should be in a similar state of charge. Also, similar cell type/size isn't a bad idea either.

The only safety problem would be a user error so just be diligent each time you are making connections. Check and double check and you'll be fine.

Eric

 

[VegasF6]

Pretty MacGyver-y :twothumbs
@vidpro check Bulgin page for part #s http://www.bulgin.co.uk/Products/BatteryHolders/BatteryHolders.html

 

[erehwyrevekool]

Very nice setup, good job ,I like it!

 

[Justin Case]

Digikey also sells the Bulgin holders.

You can fit a 26500 or 26650 in one of the Pila charging bays as-is. All that happens is that the fatter 26mm diam cell blocks access to the adjacent bay. So you can charge only one cell at a time. A workaround for that is to make a skinny wood spacer that can fit into the second bay, with conductive contacts at each end, and connect the spacer to a Bulgin holder to charge a second cell.

Yes, you can connect multiple holders in parallel and charge more than two cells at a time using a Pila. But that is going to be far from ideal. The Pila delivers a nominal 600mA current to each bay. If you connect two Li-ions in parallel, they are going to get only 300mA each (during the CC phase). So if you are going to charge something like four AW18650-2600s or four AW IMR26500s (two in parallel for each bay), you are going to wait a long time before they reach 100% SOC.