Altimeter Battery

[bill2654]

Whats the best 9v battery to use for my altimeter? I have 3 differant altimeters RRc2, Mawd, Adept22 that all use 9v power. I have heard some say they like radio shacks, some say alkiline and some say just plain duracells. I going to try my first DD this weekend and need to know what kind of batteries to buy. NO Re-chargables!

 

[dixontj93060]

I know you say no rechargeables, but I swear by the Maha Energy true 9.6V. They are great. Had a friend that worked for the Motorola cell phone battery division and he concurred.

If you are using "regular" 8.4V batteries go with Duracell (they are alkaline).

 

[Rocketman248]

I buy the cheap Eveready Gold batteries. You can get them in an 8 pack at Lowes for les than $10. I only use them for 1 or 2 flights, so no need to buy expensive ones.

 

[atxcple]

Duracells are my choice. i fly hi G's 40 -50+. they are soldered internally where others are not.

 

[quickburst]

Duracells are my choice too. Same reasons. I use them for one flight, I then recycle them into my smoke/CO alarms. I want dependable batteries in each.

I did have great success with rechargables, but they got old and I never replaced them.

 

[Viperfixr]

I know you say no rechargeables, but I swear by the Maha Energy true 9.6V. They are great. Had a friend that worked for the Motorola cell phone battery division and he concurred.

If you are using "regular" 8.4V batteries go with Duracell (they are alkaline).

I am using Duracells and also recycle them into non-rocketry uses after one flight. The thing is, they're not cheap, and sometimes I discover my stash low out at the field. I've been curious about using these 9.6V rechargeables, but I am curious how they hold up with high-G flights, that whole internally soldered thing. I could also recharge them right from my car or RV. Anyone used these on high performance flights?

 

[bill2654]

Wow, I didnt know you only get 1 or 2 flights from 1 duracell. Now I might change my mind about a rechargable system.

 

[lmt56]

I am using Duracells and also recycle them into non-rocketry uses after one flight. The thing is, they're not cheap, and sometimes I discover my stash low out at the field. I've been curious about using these 9.6V rechargeables, but I am curious how they hold up with high-G flights, that whole internally soldered thing. I could also recharge them right from my car or RV. Anyone used these on high performance flights?

Hey Mark
Not sure what you consider to be a high-G flight, but I have used the POWEREX's 9.6 v in several flights in the 15g range with no problems.
They have served me well so far and are cheaper in the long run.

 

[cjl]

Wow, I didnt know you only get 1 or 2 flights from 1 duracell. Now I might change my mind about a rechargable system.

You can absolutely get more than that - 10 flights or more is doable. The question is more about whether you want to risk a flight failure due to a cheap component. Personally, I always use brand new duracells for every flight - $5 in batteries is nothing compared to the cost of the rocket or even the propellant.

Oh, and I use duracells because they are actually soldered inside. Many other batteries are simply press-fit.

 

[GRIFFIN]

Wow, I didnt know you only get 1 or 2 flights from 1 duracell. Now I might change my mind about a rechargable system.

I'm sure you could get many more flights from them. I am a victim of a flight failure from a low battery. I think the point is 1 or 2 flights just to be safe. Is it worth several hundred/thousand dollars over a battery. I recycle mine into the Tracker reciever and kids toys. Costco now sells 9V for 13.00 for a 10 pack. That is cheap. I will only use Duracells based on the recommendations I have been given by more senior fliers.

Keep in mind the rechargable batteries add a whole new "operator error" possibility......."I thought I charged it" or "it said it was charged"

I do carry a volt meter in my flight box and check batteries to make sure they are not bad out of the box.
Also many of the altimeters will give some sort of voltage indication at power up.
(Raven beeps out nominal voltage of battery- Missleworks mini flashes Green/Yellow/Red to indicate battery voltage.)

 

[ClayD]

Battery usage is per the electronics, both in the requirement in the electronics and the voltage drop of the battery over usage.

a 9v*8.6v* duracell has something like a 45min life with full draw.

so take the draw of your electronics, and duracell produces a curve of life expectancy for the battery.

I have an altimeter that pretty much kills a 8.6v battery to 7.4 volts by the end of the flight. *7.4* is the minimum for operation.(it could be used 1 more time, but could brown out.) (although the computer battery has far less draw(and is usually 8 volts at the end of the flight.-this battery is used on a pyro battery-and NOT resuable as the computer battery)

LIPO is by far the cheapest, and most reliable batterys for this purpous*too bad i have upgraded yet*

 

[cwbullet]

I concur with Duracell.

 

[rdbones]

Duracell -

I always check the voltage efore installing the battery - Less then 9v and it does not fly. I value my rockets alot more then a $5 battery!

I thake all of the less then 9volt batteries that I have and give them to people to put in their smoke detectors! - They last a long time in those!

 

[bobkrech]

Read your altimeter instructions for the correct battery information.

The Duracell 9V battery datasheet is here. https://www1.duracell.com/oem/Pdf/new/MN1604_US_CT.pdf

Look carefully at the lifetime and current draw data. This is a pretty good indication of how long your battery will last. The information on the lower lefthand graph on page 2 give you an idea how low you an go with voltage, and the upper lefthand graph on page 2 give a rough idea of lifetime versus on current drain.

Both the MAWD and the Adept22 draw less than 10 ma and 100 mw. Their data sheets suggest that lifetimes are up to 48 hours. The MAWD uses a capacitive discharge pyrocircuit so it doesn't draw directly from the battery so it can probably go a bit longer than the Adept22 which draws the pyro current directly from the battery.

Older altimeters like the RDAS Classic use a lot more current and therefore drain the batteries much quicker. The RDAS draws 80 ma so the 1000 mw or 100 ma drain information should be looked at.

Measuring the battery voltage without a load will not give great infomation. You really want to built a test rig that temporarily puts a load resistor in parallel with the battery using a momentary switch so you can test the battery voltage under load. A 1000 ohm resistor simulates the voltage in a MAWD or Adept22, a 100 ohm resistor simulates an RDAS Classic, and a 2-10 ohm resistor simulates an e-match. I wouldn't want an altimeter battery to drop below 8 volts in a circuit, or below 5 volts when firing an e-match (or prevent computer reboots).

Bob

 

[ClayD]

Measuring the battery voltage will not give great infomation. You really want to built a test rig that temporarily puts a resistor in parallel with the battery using a momentary switch so you can test the battery voltage under load.
Bob

If your multi-meter has a 1.5v at 4ma- 9v tester at 25ma, would you think that is a good way to determine a good or bad battery.
I know if i leave the connecters on for a minuite i can see the voltage dropping by .01 ever few seconds.

this is how i measure my eveready, duracel, and chepo batteries.

my altimeter has a capacitance driven pyro circuit, with its own battery, and is the circuit that makes the battery unusable again.(for my comfort level when i measure the battery as above.)

 

[Rocketman248]

FWIW, I used the Eveready batteries in my N10,000 flight. 53Gs and the batteries worked like a charm.

 

[GregGleason]

I know you say no rechargeables, but I swear by the Maha Energy true 9.6V. They are great. Had a friend that worked for the Motorola cell phone battery division and he concurred.

If you are using "regular" 8.4V batteries go with Duracell (they are alkaline).

I have never heard of these before and they look interesting.

Have you put them on a tester to see if they really are 9V+? Do you know how robust their inside construction is?

This is making me rethink rechargeable 9V batteries.

Greg

 

[ClayD]

I have never heard of these before and they look interesting.

Have you put them on a tester to see if they really are 9V+? Do you know how robust their inside construction is?

This is making me rethink rechargeable 9V batteries.

Greg

i have seen those in plenty a rocket..one of the guys i know with that battery flew his wildman extreme with like 47g's... (dont know if that was what he was using at the time, but i know he has used them)

most nicad or nimh batteries in the 9volt size, are more than 9volt 230mah, is about as big as you can get in that configuration, mainly 200mah is the most common. most alkalyne are lower than 9volt. same with every aa aaa and c and d batteries too. its just a more active compound.

I still think lipo's (due to the technology for battery analizing) are the safest and most reliable. due to the cell balancing, and chargers that cycle charge the battery by discharging then recharging each cell.
(thats my understanding of it anyway i am not an expert of it.)

you can get a charger that works through a laptop, with battery analyzing program for 60.00 and a 11.1volt 230mah battery for 8.00 at most rc places.

 

[dixontj93060]

I have never heard of these before and they look interesting.

Have you put them on a tester to see if they really are 9V+? Do you know how robust their inside construction is?

This is making me rethink rechargeable 9V batteries.

Greg

Welded internals with seal of approval from Motorola battery guy; I also tore one apart for Robert Briody of G-Wiz as he expressed doubts--he also thought it was very well made.

Fully charged they are at ~10.4V.

 

[bobkrech]

If your multi-meter has a 1.5v at 4ma- 9v tester at 25ma, would you think that is a good way to determine a good or bad battery.
I know if i leave the connectors on for a Minuit i can see the voltage dropping by .01 ever few seconds.

this is how i measure my Eveready, Duracell, and chepo batteries.

my altimeter has a capacitance driven pyro circuit, with its own battery, and is the circuit that makes the battery unusable again.(for my comfort level when i measure the battery as above.)

From the manual of an EXTECH MN42 DVM which is probably typical.

BATTERY TEST​

CAUTION: Do not measure batteries while they are installed in the devices they are powering. The batteries must be removed from installations before tests can be made.

1. Set the function switch to the 1.5V or 9V BAT switch position. Use the 1.5V position for ‘AAA’, ‘AA’, ‘C’, ‘D’, and other 1.5V batteries. Use the 9V position for square 9V transistor batteries.​

2. Insert the black test lead banana plug into the negative COM jack. Insert the red test lead banana plug into the positive V jack.​

3. Touch the black test probe tip to the negative side of the battery. Touch the red test probe tip to the positive side of the battery.​

4. Read the voltage in the display.
....................Good,....Weak,.... Bad
9V battery... >8.2V, 7.2 to 8.2V, <7.2V
1.5V battery >1.35V, 1.22 to 1.35V. <1.22V​

The issue I have with this tester is the value of the internal load resistor is not specified so it is hard to relate the voltage value you measure to how much life is left in your battery as based on the battery data sheet. (See figure on first page of data sheet where voltage measured across a load resistor is related to hours left.) Having said that, it's far better than not having any load during a battery test as a bad battery could still read 9 volts without any load yet drop down to below 7 volts under a moderate load. (I added some wording to my previous post to emphasize that battery tests should be done under load.)

Bob​

​

 

[JDcluster]

The Adept 22 has a cap, as with most Adept altimeters. It's not as robust as some earlier models....



JD

Read your altimeter instructions for the correct battery information.

The Duracell 9V battery datasheet is here. https://www1.duracell.com/oem/Pdf/new/MN1604_US_CT.pdf

Look carefully at the lifetime and current draw data. This is a pretty good indication of how long your battery will last. The information on the lower lefthand graph on page 2 give you an idea how low you an go with voltage, and the upper lefthand graph on page 2 give a rough idea of lifetime versus on current drain.

Both the MAWD and the Adept22 draw less than 10 ma and 100 mw. Their data sheets suggest that lifetimes are up to 48 hours. The MAWD uses a capacitive discharge pyrocircuit so it doesn't draw directly from the battery so it can probably go a bit longer than the Adept22 which draws the pyro current directly from the battery.

Older altimeters like the RDAS Classic use a lot more current and therefore drain the batteries much quicker. The RDAS draws 80 ma so the 1000 mw or 100 ma drain information should be looked at.

Measuring the battery voltage without a load will not give great infomation. You really want to built a test rig that temporarily puts a load resistor in parallel with the battery using a momentary switch so you can test the battery voltage under load. A 1000 ohm resistor simulates the voltage in a MAWD or Adept22, a 100 ohm resistor simulates an RDAS Classic, and a 2-10 ohm resistor simulates an e-match. I wouldn't want an altimeter battery to drop below 8 volts in a circuit, or below 5 volts when firing an e-match (or prevent computer reboots).

Bob

 

[Handeman]

I have recently learned more about batteries, the hard way. My rocket deployed the drogue but not the main. The altimeter, a HiAlt45, was beeping out the altitude correctly when it landed hard under drogue only. Turning the altimeter off and on again and after it's start up, it indicated 8.8 volts and it beeped that it had continuity on the main ematch. The battery and the BP was removed and the ematch was touched to the battery and it fired instantly. Readings of the battery with a meter showed 8.9VDC.

The key measurement was when the meter was set to the 10A current scale and put directly across the terminals of the battery. It only read 2.2 amps. I have since found that new Duracell 9V batteries usually read in the 6+ ampere range. The low ampere output of the battery is the only thing found that might explained not firing the ematch on the main.

I have since done 6 vacuum chamber test with the altimeter and ematches reading 1 ohm. All twelve fired. Another test with the commercial ematches at 2 ohms also worked perfectly. A heads up flight to 2100 feet with commercial ematches worked perfectly.

All tests and the flight were done with the same Duracell 9V battery. The battery was reading 9.17 VDC and a discharge of 6.2 amps before the flight.

My personal test of the battery will now be the discharge rate when the meter is shorted directly across the battery. The battery will continue to fly until it reads below 5 amps discharge. At that time it gets replaced. Never again will I fly with a battery near 2 amps discharge rate, no matter what the voltage reads.

BTW, I haven't had one, but several people in my club have said they had Duracell batteries that were bad out of the box. Always test the battery, even new ones.

 

[gwolski]

I suspect my main deployment failure this past weekend at Culpeper was for the same reason. I have not tested the battery yet, but the main charge fired just fine at home after the launch. I've been checking battery voltage, but not amperage, before flights. I'll start doing both on every battery, every launch.

 

[dixontj93060]

One advantage of a known good 9.6V Powerex. Likely not to go bad. And check 'em if you want--they put out 8A easy.

Not true for all rechargeables BTW; the NMiH at Harbor Freight are piss poor and only run about half the controllers, toys and cameras in my house.

 

[gorillamotors]

Ditto on the Maha Powerex true 9.6v batteries. Outstanding batteries.

 

[MaxQ]

I suspect my main deployment failure this past weekend at Culpeper was for the same reason. I have not tested the battery yet, but the main charge fired just fine at home after the launch. I've been checking battery voltage, but not amperage, before flights. I'll start doing both on every battery, every launch.

I got in the habit of using these...but come to think...not sure I looked at amps...

https://www.batterymart.com/p-ultra...volt_battery&gclid=CM_5oNSXkqgCFQhy5QodthlcDQ

 

[bobkrech]

I got in the habit of using these...but come to think...not sure I looked at amps...

https://www.batterymart.com/p-ultra...volt_battery&gclid=CM_5oNSXkqgCFQhy5QodthlcDQ

I've used the for years. They are the best of the primary 9 volt batteries. Plenty of capacity and amps, even in cold weather. The down side is that they are 2 to 3 times the price of an alkaline, but on a $ per AH they are equal.

Bob

 

[cjl]

I've used the for years. They are the best of the primary 9 volt batteries. Plenty of capacity and amps, even in cold weather. The down side is that they are 2 to 3 times the price of an alkaline, but on a $ per AH they are equal.

Bob

They have a lot of capacity, but I've actually found that they have less current capability than a Duracell (more than most 9V alkalines though). Since I've never had a problem with capacity, I use the Duracells for the lower internal resistance.

 

[bobkrech]

They have a lot of capacity, but I've actually found that they have less current capability than a Duracell (more than most 9V alkalines though). Since I've never had a problem with capacity, I use the Duracells for the lower internal resistance.

Both have adequate current capacity under normal conditions, and a fresh Duracell has a slighlty higher initial current capability ~70F than an Untralife, however if you are on the playa in a 140 F e-bay or launching in the winter at 20F, the Ultralife will outperform the Duracell.

Bob

 

[cjl]

That's an interesting assertion - I may need to do some tests now