5v to 7.2v boost cable

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ZoomieFan
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5v to 7.2v boost cable

I’m looking for a compact voltage booster I can plugin to a regular (5v) power bank.
Required output: 7.2v, at least 2A

Chargers: 1xBasen BD01 5/5, 1x Gyrfalcon All-88 4/5, LiitoKala: 3x100 3/5, 2x202 3/5, 1x402 3/5., MiBoxer C4-12 3/5.
Flashlights: DQG Tiny III 26650 5/5, FiTorch MR35 3/5, Haikelite SC26 HD 3/5, Lumintop Tool AA/AAA 4/5, Nitecore LA10, Sofirn C01 BLF 3200k/5600k 2/5, Zebralight H600Fc 3/5.
Powerbanks: EasyAcc 26800 mAh 3/5, Xtar PB2 4/5, Xtar PB2S 5/5
Waiting for: (DQG Tiny) 21700 EDCs.

Rusty
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I’m sure somebody more knowledgeable will chime in soon, but there are a few USB buck/boost power supplies available now that would allow you to set voltage limit; just be aware that 7.2v at 2A is 14.4w, combined with overheads from the buck/boost module efficiency and you’d need a 5v power supply cable of supplying 3A+.

I recently bought this one to use as a basic 0.5-30v PSU, when plugged into a powerbank at my office desk; it’s functional if not a patch on what it could be with better UI and works up to 2A:
https://www.banggood.com/Geekcreit-USB-Boost-Module-5V-to-9V12V-Step-Up-Module-Adjustable-Voltage-Current-Display-Charging-Router-Converter-p-1503884.html?rmmds=myorder&ID=517124&cur_warehouse=CN

Hobo
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Check out this video: USB to 12V Step Up Cable – Conversion to 9V
You could buy one of these cables (this for instance, just not the 5V Version since that will just be a passive cable), do the maths and mod the resistors to fit your desired voltage.

Edit: Pulling 2 Amps from it might be a problem though, but it’s worth a shot.

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ZoomieFan
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Rusty, I think you are right, 2A is to close. On top of that, very similar looking devices stated 2A but 1A for extended use. Hobo, that’s DIY… Ooops Smile

I want something compact and in an enclosure but I’m on track of something…
Amazon

4A in.
No casing, but I like the fact it starts booting from 3v. That would mean I could build my own power with a simple battery box and some cells in parallel and/or series.
Correct me if I’m wrong but I think that will boost the overall efficiency because when using a PB there is an extra 3.6v to 5v step which hasn’t 100% efficiency.

I looked at the spec sheet from Rusty’s link and that showed that efficiency is highest when the voltage difference is smallest.
When I put two cells in series I’m at exactly the required 7.2v. So I won’t even need a step up convertor until the cells get drained and the voltage drops.
Getting somewhere Smile

Chargers: 1xBasen BD01 5/5, 1x Gyrfalcon All-88 4/5, LiitoKala: 3x100 3/5, 2x202 3/5, 1x402 3/5., MiBoxer C4-12 3/5.
Flashlights: DQG Tiny III 26650 5/5, FiTorch MR35 3/5, Haikelite SC26 HD 3/5, Lumintop Tool AA/AAA 4/5, Nitecore LA10, Sofirn C01 BLF 3200k/5600k 2/5, Zebralight H600Fc 3/5.
Powerbanks: EasyAcc 26800 mAh 3/5, Xtar PB2 4/5, Xtar PB2S 5/5
Waiting for: (DQG Tiny) 21700 EDCs.