BlackTip Batteries

[NothingClever]

Anybody have a slick voltage regulator that’s travel friendly?

I have 110v in my villa here in Saudi Arabia for charging my Dewalt batteries but had to pick up a chunky Yokohama regulator for a trip this coming weekend where the hotel only has 220v.

For those that may not have noticed, the Dewalt DCB102 charger is 110v only in contrast to most chargers these days that easily handle up to 220v and turn it into the charge your device needs. Since the BlackTip is made for travel, it’s rather key to find a slick little VR that will allow one to travel where they like (including LOBs) without worrying about frying a DCB102.

DAMHIK.

 

[NothingClever]

DEWALT FLEXVOLT 20-Volt/60-Volt MAX Lithium-Ion 12.0Ah Battery-DCB612 - The Home Depot
199$ limit2

Sale is still going on...just picked up a pair.

 

[RayfromTX]

Amazon has them for 189 and free shipping now
Ebay has them for 179.
I went with the Amazon deal for an extra set before leaving for Cozumel for 6 months.

 

[Miyaru]

Got my Blacktip from Backscatter two days ago, and have done my very first two DPV dives.

I built my own battery packs using Samsung E50 lithium-ion 21700 cells which are 5Ah and rated for 9.8A max discharge. Cost was 95 euros for 20 batteries, 28 euros for 2 housings and 1 euro for the nickel strips.

These cells are in a 5S2P configuration, allowing 19.6A maximum discharge, which means using the 8th gear is a no-go. I might create another set with 5S3P, allowing 29.6A max discharge with a total capacity of 15Ah, but that might be overkill outside of caves.

Battery pack 1 weighs 898 grams, pack 2 weighs 902 grams. Tried these yesterday without weight adjustments, but the DPV kept me dragging towards the surface.
I added extra weight to the nose with lead pellets and two extra lead blocks on the inside, total nose weight is now 2759 grams, resulting in a nose down, slightly negative buoyant DPV (in fresh water).

I ran it for 20 minutes in gears 3 till 6, voltage changed from 20.05V before the dive down to 19.48V and 19.30V after the dive. Both packs are still displaying 3 lights.


I'd love to hear what weight changes have been made to get the Travel neutrally buoyant and horizontally trimmed, for the specific battery packs you use.

 

[rjack321]

20.05V at the start for a 5s pack is only about 75% state of charge. Was there a reason to not charge to 4.1+V?

 

[Miyaru]

I took the batteries out when the light on the charger was solid red. I'll repeat it, and double check voltages before and after a dive.

 

[Miyaru]

I wrote down the voltages incorrectly. 20.5V is when the charger stops (DeWalt DCB115 charger).
Running a test right now, 1st gear continuous for 2 hours.
(higher gear will spill the water out of the crate)

Edit:

Runtime: 2 hours
Gear: 1st
Start voltage both packs: 20.5V
End voltage battery pack 1: 19.32V
End voltage battery pack 2: 19.50V

 

[geoff w]

...I'd love to hear what weight changes have been made to get the Travel neutrally buoyant and horizontally trimmed, for the specific battery packs you use.

Not possible with the Blacktip Travel tube. Neutral buoyant or horizontal trim - pick one. I personally went for neutral buoyant, as have most people I know. After 2 dives I don't even think of Blacktip horizontal trim when not underway. If you want both, get a Tech tube and be prepared for a 5 lb heavier scooter

 

[elderhome]

DIY large capacity 20V20Ah (21700 battery) for Blacktip DPV, more fun time under water!

IMG_20210422_040900

• elderhome
• Apr 24, 2021

Almost done...

IMG_20210424_171248

• elderhome
• Apr 24, 2021

20V20AH 21700 x 20 pcs. batteries

IMG_20210422_061220

• elderhome
• Apr 24, 2021

Height 101mm

IMG_20210422_061333

• elderhome
• Apr 24, 2021

Length 119mm

IMG_20210422_054620

• elderhome
• Apr 24, 2021

Building a 20V20Ah Dewalt power packs, 21700 x 20pcs

 

[geoff w]

DIY large capacity 20V20Ah (21700 battery) for Blacktip DPV, more fun time under water!
Wow! How does this even fit into a Blacktip tube? The DeWalt 12 AH batteries, which contain 21700s, don't leave much room to put in with your hand. And how do you keep this configuration from making a Blacktip Travel very negatively buoyant?