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atufte

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Is it possible to use a 3.7 V 9600mAh battery in the M8/9?, i have a friend who makes custom batteries to almost anything, and since the only thing that really sucks BIG time with the M8/9 is battery capacity, i would really love to be able to make a longer lasting battery, like the ones i got in my 5D MKII's...

 

Anyone have a clue?, i'm a real nub with voltage and stuff like that, so i would like to get an opinion from some more skilled persons in this area...

 

Thanks in advance...

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Is it possible to use a 3.7 V 9600mAh battery in the M8/9?, i have a friend who makes custom batteries to almost anything, and since the only thing that really sucks BIG time with the M8/9 is battery capacity, i would really love to be able to make a longer lasting battery, like the ones i got in my 5D MKII's...

 

Anyone have a clue?, i'm a real nub with voltage and stuff like that, so i would like to get an opinion from some more skilled persons in this area...

 

Thanks in advance...

 

Technically, as long as it puts out a voltage matching the standard battery and provide enough amps (not amp/hours) to match the demand it should work.

 

BTW, I am also a bit disappointed in the M8 battery life - especially since I have to take the bottom plate out, which means taking off my Luigi half-case, etc. It's quite a production compared to my Digilux 2 - where it takes 5 seconds. Having said that, I am not sure that I'd prefer a larger/heavier battery.

 

Alberto

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Is it possible to use a 3.7 V 9600mAh battery in the M8/9?...

Alexander,

 

The voltage is right so that won't cause you a problem but the number of Ampere-hours will govern the mass of the battery so you'll need to make sure that it will physically fit into the battery compartment.

 

The Leica M8 battery has a capacity of 1900 mAh so a 9600 mAh battery will be around 5 times the size and won't fit into the camera. You could possibly use this in a clip on belt pack or in a backpack but you'll have to connect it your M8/9 with a lead, which will introduce a significant volt drop unless it's very, very thick or very short. The inherent volt drop may affect the operation of the camera especially where a lot of power is required (shutter re-cocking) and a portion of your extra battery capacity will be devoured by the volt drop in the battery lead.

 

Something else to consider is warranty, which would be invalidated by using a non Leica approved battery. Since it's a Lithium-Ion battery you need to make sure that your friend has included the correct safety circuitry to prevent the battery from exploding or catching fire.

 

Please let us know what you decide to do. :)

 

Pete.

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A 9600mAh battery is capable of dumping a hell of a lot of current in a fault condition so could cause carnage in your camera should a fault or short develop on the main board in the camera. Also it would take many more hours to charge the battery....also as already said your warranty could be compromised... this would be an overkill.

 

Nigel

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Thanks for the feedback guys, but i eventually think of converting a 5D MKII battery to M8, but do you know if it's the battery that's bad or the power control in the M8?, since the M8/9 battery is 3.5V 1900 mAh and the 5D MKII battery is 7.2V 1800mAh, i get if i'm lucky 200 shots with my M8 and the other day i got 1787 shots from a single charge on my 5D MKII, no that's more like it...

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Alexander,

 

TBH, I don't have a problem with battery power in my M8 and I've very rarely needed to change a battery during a days shooting and filling a 8GB card. You may find that changing some settings significantly increases your battery life. I normally shoot DNG only (so there's no power used to process in-camera jpegs) review is set to 3 secs (but you could shut it off to save more power) I'm in the habit of flipping the On switch to Off between shots rather than allowing the auto shut off to kick in, and I don't delay the shutter re-cock with discreet mode unless I'm in a church etc. So I don't think that either the battery or the power management in the M8 is particularly bad.

 

I, too, have a 5D2 and I find that I'm changing its batteries more frequently than with my M8 but I'm happy with that because of the way I use my 5D2. I normally use it on a tripod with R lenses for macro and telephoto work so I'm constantly using Live View to nail focus, which chews through the battery because it has to constantly keep the 920,000 dot LCD screen lit.

 

Pete.

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Alexander,

 

TBH, I don't have a problem with battery power in my M8 and I've very rarely needed to change a battery during a days shooting and filling a 8GB card. You may find that changing some settings significantly increases your battery life. I normally shoot DNG only (so there's no power used to process in-camera jpegs) review is set to 3 secs (but you could shut it off to save more power) I'm in the habit of flipping the On switch to Off between shots rather than allowing the auto shut off to kick in, and I don't delay the shutter re-cock with discreet mode unless I'm in a church etc. So I don't think that either the battery or the power management in the M8 is particularly bad.

 

I, too, have a 5D2 and I find that I'm changing its batteries more frequently than with my M8 but I'm happy with that because of the way I use my 5D2. I normally use it on a tripod with R lenses for macro and telephoto work so I'm constantly using Live View to nail focus, which chews through the battery because it has to constantly keep the 920,000 dot LCD screen lit.

 

Pete.

 

My main problem is the cold, (i live in Norway) i regularly use a heat patch under the bottom plate, but this is far from ideal, and annoying to have to do this to say at least, the other day i got 30 shots on a fully charged original battery, in -18C, (forgot the heat patches at home, along with my 3 spare original batteries), this is really boring, and i also shot DNG only, never use preview, and have AUTO power off on 1 min. So i'm screwed anyway, but back to my original question, will i get more exposures with a modified 5D MKII battery? (i'm making a slot mount like the one on the 5D MKII charger under a spare M8 baseplate, with a very short power cable from battery, over to the modified M8 flip out battery connecting in the battery slot in a similar way like a Canon/Nikon battery grip, just way smaller, i might even make a slot for two 5D MKII batteries under the plate, since it can fit two, and i can use it, when i need the extra power (i'm very often in the tundra in Iceland , working mainly with 5D MKII's but would love to be able to use my M8, but without the patch, and even with it need like 5 batteries for a few hours...)

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One of the firmware updates a while ago fixed the problem by shutting off any minor current draw when the camera is off. Battery life got much better for me but I don't blast away taking thousands of pictures in one session. Having a second and third battery ready for use would be my solution.

 

As battery technology gets better I'll bet that higher capacity batteries for the M8 will be available. Unfortunately today the high cap and light batteries can catch fire spontaneously.

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Alexander,

 

Okay, I see, the cold is causing you problems with battery capacity. The 5D2's battery has 5 times the capacity of the M8's battery so I'd expect it to last longer.

 

Your 5D2's batteries have a voltage of 7.2 Volts so if you manage to attach them to your M8, which only wants 3.7 Volts, you risk frying the M8's motherboard. You could use a resistor to drop the voltage across the 5D2 battery's output to 3.7 Volts but the resistor will burn up about half the battery's capacity instead of it going into your M8 (although the right type of resistor will transform the energy into a little heat for you).

 

Please be aware that this would be a potentially very risky thing to do and you should find a competent Engineer if you choose to do it. :(

 

Pete.

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Alexander,

 

Okay, I see, the cold is causing you problems with battery capacity. The 5D2's battery has 5 times the capacity of the M8's battery so I'd expect it to last longer.

 

Your 5D2's batteries have a voltage of 7.2 Volts so if you manage to attach them to your M8, which only wants 3.7 Volts, you risk frying the M8's motherboard. You could use a resistor to drop the voltage across the 5D2 battery's output to 3.7 Volts but the resistor will burn up about half the battery's capacity instead of it going into your M8 (although the right type of resistor will transform the energy into a little heat for you).

 

Please be aware that this would be a potentially very risky thing to do and you should find a competent Engineer if you choose to do it. :(

 

Pete.

 

It will of course have a chip to convert from 7.2v to 3.7v, but he told me i would not loose any of the power from the battery by this chip, in fact he told me since it use less power it will give even more power (longer) to a M8 than a 5D MKII, but again i know nothing about these things...but i hope this is correct..

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It will of course have a chip to convert from 7.2v to 3.7v, but he told me i would not loose any of the power from the battery by this chip, in fact he told me since it use less power it will give even more power (longer) to a M8 than a 5D MKII, but again i know nothing about these things...but i hope this is correct..

Interesting. It sounds as if he's intending to invert the 7.2 Volts dc from the 5D2 battery into 7.2 Volts ac and then use a switch mode power supply to produce 3.7 Volts dc. This is the only way I can think he could do it without using a resistor as I mentioned above to create a volt drop and waste power in the process. I'm not aware of such an arrangement on an off-the-shelf integrated circuit board that would fit into the M8's battery casing along with the Li-Ion material so he may intend to use a custom designed one (which sounds expensive).

 

Good luck and please let us know how it goes. :)

 

Pete.

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Interesting. It sounds as if he's intending to invert the 7.2 Volts dc from the 5D2 battery into 7.2 Volts ac and then use a switch mode power supply to produce 3.7 Volts dc. This is the only way I can think he could do it without using a resistor as I mentioned above to create a volt drop and waste power in the process. I'm not aware of such an arrangement on an off-the-shelf integrated circuit board that would fit into the M8's battery casing along with the Li-Ion material so he may intend to use a custom designed one (which sounds expensive).

 

Good luck and please let us know how it goes. :)

 

Pete.

 

We will not do all this inside the original M8 battery shell, we will make a circuit board inside (or outside) the replacement M8 base plate, so the M8 battery will be emptied an replaced with the connection to the circuit board and the LP-E6 battery slot...

 

New post from today:

 

galerielux | welcome

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To keep it simple just place a few diodes in series to drop the voltage. Four or five should do it. But why don't you gang together a few Lieca batteries in a holder if you are prepared to carry extra weight.

 

I keep coming back to having an extra battery in your warm pocket for those times when you need it. That's still the best solution in my opinion.

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Alexander,

 

Since the M8 and 5D2 batteries are roughly the same size it just occurred to me to check the capacity of one of my (proprietary) Canon 5D2 batteries, which is 1800 mAh.

 

Where did your quoted figure of 9600 mAh come from?

 

Pete.

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Alexander,

 

Since the M8 and 5D2 batteries are roughly the same size it just occurred to me to check the capacity of one of my (proprietary) Canon 5D2 batteries, which is 1800 mAh.

 

Where did your quoted figure of 9600 mAh come from?

 

Pete.

 

It came from a confused mind ;-)

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I know that feeling well ... :o

 

Pete.

 

I have now made a baseplate with a connector to the battery, (removed the battery in it's case an transferred the battery connectors inside the battery case to the outside through the M8 baseplate, and

kept the circuit board in the battery for the measurement/reading in the display, now it's time to buy a LOOOOOOOOOOOONG lasting rechargeable 3.7V XXXXXmAh, i really need some tip on this one...

 

I tried with a 12V adjustable battery eliminator and it worked fine, so i'm also making a plug for this

one for both charging and the possibility of connecting to a wall socket (not that i'm gonna use it;-)

ANd BTW, all my original M8 batteries measure 4.2V not 3.7V as is says in the specs...

 

So now the question, can i use these batteries, even if they differ in mAh? ANd what will

be the best possible battery for a long lasting shoot...(i will use the whole surface of the base

from one end to the baseplate lock so it's a lot of space to fit a good size battery.

But i will try to keep it smaller than a motor drive and not much bigger than a Leicavit)

 

What about these batteries?

 

Your Online Source For 3.7V 6600 mAh Li-Ion Battery Pack - With Protection IC

 

Rechargeable Batteries & Battery Chargers - Polymer Li-Ion Battery, 3.7V 5000mAh (7550140)

 

Rechargeable Batteries & Battery Chargers - Polymer Li-Ion Battery, 3.7V 10000mAh

 

Rechargeable Batteries & Battery Chargers - Li-Ion 18650 3.7V 5200mAh Stick Rechargeable Battery module with 20AWG Bare Leads(Customize)

 

Rechargeable Batteries & Battery Chargers - Li-Ion 18650 3.7V 4400 mAh Rechargeable Battery module with PCB

 

Thank for all the help....

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