Hi all, I own two Subtronic Alpha 160 pro fusion, which I really love because of its power, light quality and size. for me the handicap of this flashes is its batteries, they are dedicated and I don't really like it. The main thing that I don't like about it it's the charger, only a red or green led to know if they are charged or not. Several times I have noticed issues with the charger, I connect the batterym switch the power on and after 15 minutes turns green, It feels strange, so I restart the procedure and this time  the battery is charging for 2 hours. If i don't notice I'll run out of batteries in 10 pictures the next dive, Presumibly just before you find an Orca having sex with a whale shark. 

So as I was tired of the situation I planned to do on myself new battery packs that I can control the cells individually in a normal charger. Then I noticed than the original battery packs are simple as two 18650 cells connected in series, so they give 7,4 volts (nominal). So I decided that if I am going to do it I want to not charge batteies in a day during a trip, tipically 4 dives. So I made my packs with two packs of two 18650 batteries connectd in parallel, so I double de mah. resulting in this packs you can see in the pictures.

I made the design and went to a turner to make the pack with the threads and the o'ring channels, I bought the cables with the conector already welded from Subtronic and I bougt the battery holders from Aliexpress, sended the alluminum pack to anodize and I got the cable penetrators from BlueRov  which i had to modificate a little bit in order to hold 6.5 mm cable. 

It's been a bit expensive, around 300 euros each plus my time and my job, but I can control every cell one by one, but everytime I go to the water I am absolutely sure they are perfectly charged, if any of the cells it's damaged i can change it for a ridicculous price comparing with a wole pack, and I can do on myself in seconds. The contra is that this battery packs are big. So now I am planning to make another packs with only to cells in serial connection, ir order to make it thinner, to use it when at home and tipically dive once or two a week.

The connector is an S4, so if Seacam uses the same voltage this would also work with them

gran idea,pero me temo que Arturo Telle ya pensó en eso,en su web idiving ofrece una bateria propia mas pequeña y manejable a un precio muy interesante,saludos...

42 minutes ago, FOTOSUB said:

gran idea,pero me temo que Arturo Telle ya pensó en eso,en su web idiving ofrece una bateria propia mas pequeña y manejable a un precio muy interesante,saludos...

Better in english, so anyone can understand. I have 4 Idiving batteries, are exactly the same than the Subtronic ones but smaller, nothing else. Subtronic sells batteries that works also as an arm (which I don't like) and they also have batteries with no balls, like the idiving ones, in order to put it in the side of the strobe in the neoprene protector. The difference between the Subtronic and the Idiving is only the size, Idiving is smaller and slightly cheaper. But both share the same issues. They need the Subtronic dedicated charger, when the cells become older you have to buy brand new batteries, 2 18650 good quality battery cells are 40 euros worth as much, the whole battery is 200 euros worth if Idiving and 250 euros if Subtronic.

My batteries are absolutely different focused. My goal is manufacture a housing for batteries that I can change the cells in seconds, so when the cells are old I swap them by new ones for a few euros, I can use normal chargers and I double the number of cells, so I can make 4 dives with no changing battery. But I recognize that if I had to do again I would make a design for only two cells.