13.5 hour battery for the dvx

jenningsp

jenningsp

Well-known member
i have this idea that i can build a 13 hour battery for the dvx.

how it works....

current battery stats

5600mAh
7.2V
lasts 5 hours

that's the best battery you can buy.

i want to make a

15000mAh
7.2V
lasts 11.2 to 13.5 hours (worked this out using the stats in http://www.dvxuser.com/articles/battery/ )



concept......

get 6 rechargable 1.2V AA 2700mAh NiMH batteries
put them in a series - in a little battery box from an electronics store

get my old 800mAh battery that lasts 30min, take it apart and just use the connection to the dvx face plate. attach the battery pack to this.

there you go! a battery that will last 13 hours and you can use your existing charger!!!!!!!

or take out the batteries and charge them in a AA charger while you're using the other 6 AA's you bought in the 12 pack!!!!!!!!

the whole thing is about the same size as the ordinary battery and will cost around $30 all up - maybe cheaper


i haven't made it yet but i think it will work......... if any body can see a problem please tell me.
 
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you've got me paranoid here.... you might be right.
i thought it was all about the amps and volts
regardless of the tech used for holding the power... it's still power.
but then again i am just a beginer when it comes to electronics.
can you give us some of the stats from the two batteries you used??? amps and volts and anything else?
 
Putting them in series will you yield you 2700mAh.

Parallel is what you want if you want to increase the amperage.
 
jenningsp said:
concept......

get 6 rechargable 1.2V AA 2700mAh NiMH batteries.......if any body can see a problem please tell me.
Click to expand...

Problem is, your math is flawed! :)

6 x AA 1.2V/2700mAh will give you a 7.2V/2700mAh batterypack or a 1.2V/16200mAh battery pack. Both would be about ~20Wh, whereas the Spec-Comm or DVXuser battery is about ~40Wh; that's DOUBLE the capacity for the DVXuser/Spec-Comm battery.

You'd need 36 AA batteries to get what I think you are expecting, which is a 7.2V/16.8Ah battery. Using 36 AA is completely unsuitable, and VERY heavy/bulky.
 
after some research on the net i think the only difference between the two types is

li-ion will last 3 years with 500 charges
nimh will last 5 years with 300 charges
li-ion will have 90% of it's charge after 30 days
nimh will have 60% of it's charge after 30days


so to counter this you charge the batteries the day before you're going to use it and buy another 6 AA's in the future (and that's the future like in 2 years)

if anybody has anything to ad please do
 
HAHAHAHHAHAHAHHAHA

damn i thought i was onto something. i'll have a completely useless brick.
i think this is why i failed physics

thanks guys.
 
one thing though.....

you can get 36 of them for around $80
put them on a belt around your waist or in a backpack and have a nice little springy telephone cable going to your cam.

could be kinda cool???
 
aprox 30 grams each - a bit less


12 AA's

5400mah
7.2v
360g ~ 0.8 pounds
= $30 - maybe cheaper
aprox 4.5 hours use

or

36 AA's

16200mah
7.2v
1kg ~ 2.2 pounds
= $80 - maybe cheaper
aprox 13 hours of use

if you had the 36 AA's on a canvas ammunitions belt it wouldn't be that bad. you could even use the belt for other things as well - like ammunition :)
 
I like this idea.

Call it the Bandolera de la Energía !™ <--- But you CAN'T because I own this trademark now...

How about a high-capacity laptop battery?

Or those battery packs for mountain bikes - they fit in the bottle cage - lotta juice in those things.
 
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Okay, now, see -- the bandolier brings some style to it. Make it look like Chewbacca's bandelier. Call it ChewBattery or something like that... :thumbsup:
 
Then you'd have no choice but to wear two of them, criss-crossing your chest... it makes me think of that SciFest entry where the DVX was a gun :)

This has turned into just about the funniest thread I've seen here in a while.
 
Your idea is much easier to accomplish with 'dead' laptop batteries, instead of AAs. Typically, there's only one or two dead cells, the rest are fine. About a year ago, I've disassembled a DELL battery (8 cells), six were fine, so I put 3 pairs in parallel (each cell is 3.6V - actually, it's 4.2V when you measure the voltage, but they're rated as 3.6V), attached a nice coiled phone cord, and shoved them into a tiny pouch that I wear on my belt. I cut the camera end off the charger's cable, and made a 'universal' adapter out of RJ-45s I had, so now I can charge this pack with my camera's charger.
 
Just be careful when experimenting with Li-Ion batteries that you don't remove "the chip". All Li-Ion batteries use a chip to limit charging rate, discharge rate and amount of discharge. Usually the chip is designed to handle a particular number of cells. Usually this IC is designed to fry itself if certain parameters are exceeded, to prevent the cells from damage or explosion. They are also much more sensitive to heat (relative to NiCad or NiMh) so you need to be very careful when soldering them.

If you want to make custom packs, you can obtain proper limiting chips. There is always the possibility that for a particular battery pack/charger combination the protection logic lives in the charger and not the cell, so you need to make sure before hacking on them.


Additonal note: Li-Ion cells will most likely explode if you:

Short them out.
Reverse polarity.
Heat over 100C.
Look at them funny.
 
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I was just watching the thread untill it got real serious :-)
In addition to what tigeba said, keep in mind that you really do not want to deal with the Li-Ion cells unless you know exactly what you are doing. Even that does not always help judging by the recent history of the Apple and Dell laptops blowing up. To stress the point, one can not just buy a Li-Ion cell retail or mail order, as there are no vendors who are ready to take a risk of sending them without a proven protection circuit integrated in the pack. Each newly designed Li-Ion pack goes through long safety tests, making sure overcurrent/overvoltage conditions do not cause an explosion. As far as charging the LI-Ion packs, the charge voltage has to be exactly right at 4.2V/cell +/- .5%
Overcharging just a little would result in damage, undercharging by 1% results in 10% capacity loss...
 
Just get a second Panasonic battery like I did and you are sorted. It won't lose you any precious recording if you can just turn off the camcorder and replace the battery. Most people here do some sort of shorts or indie films and the scenes are all set up and you can start and stop shooting anythime. The only time I think you need a 13.5 hrs battery pack is as if you are recording a guiness world record of say David blaine doing his stunt and you wnat to proove that he didn't just stop the camera and start all over again. Even then your 13.5 hrs battery pack will not be enough as his trick takes 24 hours or more to finish.

But good effort anyway.
 
i found a place that sells 40 AA's for $70

in the future when the batteries need replacing, the tech can only improve -
nimh will have this new sanyo tech that makes them better in every-way to li-ion except for weight to capacity ratio.
there capacities will increase.
and they'll jest get cheaper.

so for around the same price it costs to buy a dvx battery - $79 + $15 post
you could make a ChewBattery or ChewbaccaBand or Band-alia-chew or band-de la-Chew

you could also have a model called 'the brick' or 'the black box'
a box weighing 1kg ~ 2.2 pounds of raw power. put it anywhere
on your belt like a wireless mic kit
in your back pack
on the shoulder mount rail system as a counter weight instead of a huge metal hunk.
at the bottom of your steady cam as a weight..
 
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re alex

it's not about why, it's about being able to.

why build your own 35mm adapt when you can buy an M2?
 
For safety reason, I would suggest spending the money and getting a few of the DVX battery and build a rig to accept all the DVX batteries in Parallel. You dont wnat to connect them in series as this will increase the amp and fry the DVX.

I agree with your comment. No harm to try. But when it comes to battery and especially Li-Ion, we have to be extra careful here. Wrong connection and soemthing gets burnt. I tried rigging up my palmtop with a new li-ion battery after the original one went dead, i think i made a fatal mistake of connecting the lead wrongly, the battery is busted and I think the palmtop is gone too. havent tried it since.
 
I got 8 spec-comm batteries, 2 panasonic batteries, and a dolgin 4 bay turbo charger with my 2 hvx's. I can charge 4 batteries at once in about 2-3 hours, and can hot swap them in and out of the charger. What more does one need :)

Jason
 
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