# Battery powered charger to plug in a DC brick? **URL:** \ **Category:** Factual Questions\ **Created:** [June 7, 2013, 7:09pm UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412 "2013-06-07T19:09:50Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Rhythmdvl](https://avatars.discourse-cdn.com/v4/letter/r/85f322/32.png) [@Rhythmdvl](https://boards.straightdope.com/u/Rhythmdvl)\ **Post date:** [June 7, 2013, 7:09pm UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412/1 "2013-06-07T19:09:50Z")
We have an awesome little battery-powered device that we’re taking with us to a few music festivals this summer. It’s so awesome that there’s a pretty high likelihood that its battery will need recharging at least once. We have a battery-powered charger, but it’s only got a USB port. The unit in question’s charging base only has a DC brick to plug in. Since we’re driving, weight isn’t an issue and can bring any additional batteries needed (e.g. D cells or lantern batteries; the unit’s battery isn’t user-accessible). We do have an inverter that plugs into the car, but that’s entirely too cumbersome to do at a music festival. We’d like to charge it overnight when it’s not in use. I can’t imagine this isn’t a common device, but I can’t seem to find the right product—everything either has a USB port only or is powerd by a car aux port. ETA: According to the folks who make the device, the car charger they’re working on requires 9v 1.3a. Anyone? ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [June 7, 2013, 7:30pm UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412/2 "2013-06-07T19:30:21Z")
Does this device have a dedicated charging base? What do the charge contacts look like? Do you know the charge input voltage and current? ---
**Author:** ![Rhythmdvl](https://avatars.discourse-cdn.com/v4/letter/r/85f322/32.png) [@Rhythmdvl](https://boards.straightdope.com/u/Rhythmdvl)\ **Post date:** [June 7, 2013, 7:41pm UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412/3 "2013-06-07T19:41:43Z")
The [device](http://www.ploom.com/pax) has its own [charging base](http://www.ploom.com/store/media/catalog/product/cache/1/thumbnail/040ec09b1e35df139433887a97daa66f/c/h/charger_1.png), which is custom-fit to the item (i.e. can’t use a charger for a different item). The charger plugs into the wall–it’s the wall-plug-to-charger bit that’s giving me trouble. I can find battery-powered chargers that have USB and similar ports, but none that will take a standard plug. ETA: The only information I have at the moment is that a car charger should put out 9v/1.3 amps. Their customer service reps are fantastic, so if that’s not the right info I can always ask. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [June 7, 2013, 7:57pm UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412/4 "2013-06-07T19:57:41Z")
Hmm… Does the charge brick plug into the charger base, or is it hard-wired? If it plugs in, you (by that I mean _I_) could design a DC-powered supply that would work. If it’s hard-wired, you would need to cut the cord and splice on a connector. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [June 7, 2013, 8:00pm UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412/5 "2013-06-07T20:00:20Z")
Using something like this: > **[FOR 9V 2.2A Mintek ADPV18A AC ADAPTER Car Auto Mobile CHARGER DC SUPPLY CORD ...](https://www.ebay.com/itm/FOR-9V-2-2A-Mintek-ADPV18A-AC-ADAPTER-Car-Auto-Mobile-CHARGER-DC-SUPPLY-CORD-/390603603698?pt=LH_DefaultDomain_0&hash=item5af1c9fef2)** > > Find many great new & used options and get the best deals for FOR 9V 2.2A Mintek ADPV18A AC ADAPTER Car Auto Mobile CHARGER DC SUPPLY CORD at the best online prices at eBay! Free shipping for many products! ---
**Author:** ![Rhythmdvl](https://avatars.discourse-cdn.com/v4/letter/r/85f322/32.png) [@Rhythmdvl](https://boards.straightdope.com/u/Rhythmdvl)\ **Post date:** [June 7, 2013, 8:13pm UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412/6 "2013-06-07T20:13:18Z")
The brick is detachable from the charging base, if that helps. What would it take to design a DC-powered supply? Is this something that could be put together from Radio Shack parts? ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [June 7, 2013, 8:14pm UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412/7 "2013-06-07T20:14:28Z")
So basically, you want a portable battery pack that outputs 120V AC? They exist, but they are usually large devices [like this](http://www.amazon.com/Schumacher-XP2260-Instant-Portable-Source/dp/B004EIAADG/ref=pd_sbs_auto_2). ---
**Author:** ![Rhythmdvl](https://avatars.discourse-cdn.com/v4/letter/r/85f322/32.png) [@Rhythmdvl](https://boards.straightdope.com/u/Rhythmdvl)\ **Post date:** [June 7, 2013, 8:22pm UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412/8 "2013-06-07T20:22:00Z")
I’m not exactly sure what I want. The linked unit seems to be ready to power just about anything you can plug into it. I just want to charge this battery-operated device, which I’m pretty sure (or hopefully sure) doesn’t need the whole 120V AC. Here’s our [battery](http://www.coleman.com/product/cpxtrade-6-portable-electronics-charger/2000002673) charger for USB items. It takes 4 D-Cells and lets us plug a USB into it. Besides lacking a standard receptacle, it only puts out 5 volts (or so I assume given how that’s printed on the face). I want to find something very similar, but has a way to plug this charger in (or has an output that will plug into the charger’s base) and puts out the 9 volts/1.3 amps. ---
**Author:** ![dstarfire](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dstarfire/32/5762_2.png) [@dstarfire](https://boards.straightdope.com/u/dstarfire)\ **Post date:** [June 7, 2013, 8:50pm UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412/9 "2013-06-07T20:50:42Z")
Maybe something like this will work?: [http://www.amazon.com/Xantrex-802-1500-XPower-Portable-Powerpack/dp/B00005RHQQ/](http://www.amazon.com/Xantrex-802-1500-XPower-Portable-Powerpack/dp/B00005RHQQ/) Aside from that, try searching the web for “power pack” and AC. (Include the quotes around power pack so it searches for those words as a unit) ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [June 7, 2013, 8:53pm UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412/10 "2013-06-07T20:53:56Z")
> [@Rhythmdvl](#): > > The brick is detachable from the charging base, if that helps. What would it take to design a DC-powered supply? Is this something that could be put together from Radio Shack parts? I think the device I liked to on ebay is what you want. ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [June 7, 2013, 9:59pm UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412/11 "2013-06-07T21:59:53Z")
> [@Rhythmdvl](#): > > I’m not exactly sure what I want. The linked unit seems to be ready to power just about anything you can plug into it. I just want to charge this battery-operated device, which I’m pretty sure (or hopefully sure) doesn’t need the whole 120V AC. If it’s a “DC brick” designed to plug into a wall outlet, then yes, it really does need 120V AC. It needs very little _current_, but it still needs the full 120 volts of _voltage_. (Well, maybe just 100 V, but that doesn’t really help you.) ---
**Author:** ![Rhythmdvl](https://avatars.discourse-cdn.com/v4/letter/r/85f322/32.png) [@Rhythmdvl](https://boards.straightdope.com/u/Rhythmdvl)\ **Post date:** [June 7, 2013, 10:26pm UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412/12 "2013-06-07T22:26:41Z")
> [@beowulff](#): > > I think the device I liked to on ebay is what you want. Forgive me if I’m missing something (or my explanations have been unclear), but that seems to leave me in a similar place as I am now–what to plug it in to. The parking lot is a short distance from the campgrounds, but we’d rather not head to the car and sit around for a few hours (accessory lighter socket only works with the key to acc or on). I basically want to take _X_ 9-Volt batteries (or whatever would be appropriate), stick them in a box that connects them in series, add an LED or two to make it look cool, then wire it to a standard receptacle that I can plug in to. Since I’m having a hard time explaining in words, here’s a [crappy picture I drew](http://imgur.com/wYPi8MI)and uploaded to Imgur. ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [June 7, 2013, 10:39pm UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412/13 "2013-06-07T22:39:42Z")
You said you already had an inverter that plugs into a car. That’s what the “mystery circuit” in your drawing needs to be. And the product I linked to earlier is exactly what you’re describing. ---
**Author:** ![Rhythmdvl](https://avatars.discourse-cdn.com/v4/letter/r/85f322/32.png) [@Rhythmdvl](https://boards.straightdope.com/u/Rhythmdvl)\ **Post date:** [June 7, 2013, 10:41pm UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412/14 "2013-06-07T22:41:52Z")
> [@scr4](#): > > If it’s a “DC brick” designed to plug into a wall outlet, then yes, it really does need 120V AC. It needs very little _current_, but it still needs the full 120 volts of _voltage_. (Well, maybe just 100 V, but that doesn’t really help you.) Ah, I see. Since the plug and charging base can be separated, can I use batteries to directly charge it? Batteries are DC, right? That’s why so many items have battery power and a DC brick. ---
**Author:** ![arseNal](https://avatars.discourse-cdn.com/v4/letter/a/ecae2f/32.png) [@arseNal](https://boards.straightdope.com/u/arseNal)\ **Post date:** [June 7, 2013, 10:45pm UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412/15 "2013-06-07T22:45:53Z")
If you want to Radio Shack it, this might work [http://www.instructables.com/id/Portable-Battery-Powered-ACDC-Power-Source/](http://www.instructables.com/id/Portable-Battery-Powered-ACDC-Power-Source/) Here’s a hand-crank power supply, and it has a normal AC-style outlet on it, but oddly, it puts out 120V DC, not AC. That’s weird. [http://www.amazon.com/K-TOR-Pocket-Socket-Generator-Portable/dp/B00658Z3UI](http://www.amazon.com/K-TOR-Pocket-Socket-Generator-Portable/dp/B00658Z3UI) ---
**Author:** ![Rhythmdvl](https://avatars.discourse-cdn.com/v4/letter/r/85f322/32.png) [@Rhythmdvl](https://boards.straightdope.com/u/Rhythmdvl)\ **Post date:** [June 7, 2013, 10:49pm UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412/16 "2013-06-07T22:49:38Z")
> [@scr4](#): > > You said you already had an inverter that plugs into a car. That’s what the “mystery circuit” in your drawing needs to be. And the product I linked to earlier is exactly what you’re describing. Aw man, I’m making a mess of this thread. The “Instant Portable Power Source” is pretty much what I’m looking for but at a much larger scale. It looks like I could plug any AC machine into it. Since the DC brick and the charging station are detachable, I’m hoping it’s my verbal clumsiness that’s mucking things up, not the lack of existence. How many 9v batteries would it take to generate 1.3 amps (if that question makes any sense electricity-wise)? Too many to make a useful portable device? ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [June 7, 2013, 10:53pm UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412/17 "2013-06-07T22:53:59Z")
> [@Rhythmdvl](#): > > Forgive me if I’m missing something (or my explanations have been unclear), but that seems to leave me in a similar place as I am now–what to plug it in to. The parking lot is a short distance from the campgrounds, but we’d rather not head to the car and sit around for a few hours (accessory lighter socket only works with the key to acc or on). > > I basically want to take _X_ 9-Volt batteries (or whatever would be appropriate), stick them in a box that connects them in series, add an LED or two to make it look cool, then wire it to a standard receptacle that I can plug in to. > > Since I’m having a hard time explaining in words, here’s a [crappy picture I drew](http://imgur.com/wYPi8MI)and uploaded to Imgur. That device gets you from 12v to 9v. Now, all you need is a 12v battery (and a cigarette lighter socket). If your gadget really takes 1.3A, you are going to need some hefty batteries to charge it. C-cells can deliver 8 amps for an hour (optimistically), so you could, in theory, just use 6 of them in series to power your device. You would need to get the correct charger plug. ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [June 7, 2013, 11:00pm UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412/18 "2013-06-07T23:00:43Z")
> [@Rhythmdvl](#): > > Ah, I see. > > Since the plug and charging base can be separated, can I use batteries to directly charge it? Batteries are DC, right? That’s why so many items have battery power and a DC brick. So there’s a power supply that plugs into the wall, right? And this power supply has a cord with a connector on the end, which plugs into the charging base? Yes, you could build a battery pack that replaces this power supply. But there is no standard for the connector, so unless you’re lucky enough to find an identical connector at your local Radio Shack, you’ll have to use the one you have, and cut the cord and connect it to a battery pack. And you need to build a battery pack that matches the voltage of your power supply. So what _is_ the output voltage and current of the power supply? You mentioned 9V/1.3A but that sounds really high for something like this. What makes me nervous is the fact that we have no way of knowing how accurate the DC voltage needs to be regulated. And your “device” has a lithium-ion battery in it, so if you charge it incorrectly, it will explode. Most likely the circuitry in the charging base will prevent that, but I would be very careful and at least include a voltage regulator as part of the battery pack. ---
**Author:** ![Rhythmdvl](https://avatars.discourse-cdn.com/v4/letter/r/85f322/32.png) [@Rhythmdvl](https://boards.straightdope.com/u/Rhythmdvl)\ **Post date:** [June 7, 2013, 11:46pm UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412/19 "2013-06-07T23:46:30Z")
I \*think \*I’m starting to see the issues here. I guess I’ve been spoiled by multi-battery what seem to be high-powered devices. Our tent has a self-inflating, 12" tall _air mattress_ and we’re bringing a giant fan powered by 8 D-cells (remember, this it’s a music festival and we’ve got car to get there). What about\*\* arseNal’s\*\* link? Hooked up to an inverter or a car lighter socket to use\*\* beowulff’s\*\* link… ---
**Author:** ![jnglmassiv](https://avatars.discourse-cdn.com/v4/letter/j/f07891/32.png) [@jnglmassiv](https://boards.straightdope.com/u/jnglmassiv)\ **Post date:** [June 8, 2013, 1:16am UTC](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412/20 "2013-06-08T01:16:05Z")
You definitely do not want to use an inverter just to bring 12VCD up to 120vac to use an AC adapter to get 9VDC. Skip the lossy inversion and use **beowulff’s** adapter with a 12v battery [like this](http://www.globalsources.com/gsol/I/VRLA-battery/p/sm/1043895774.htm) and a [Radio Shack lighter jack](http://www.radioshack.com/product/index.jsp?productId=3889591). You could also use your 8 D cell mattress inflater battery. I wonder what the power draw actually is on the device, both for battery charging and during use. 1.3A seems high. [Next page](https://boards.straightdope.com/t/battery-powered-charger-to-plug-in-a-dc-brick/660412.md?page=2)