9 volt alkaline vs lithium

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qquake2k

Captain Low-N-Slow
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What are your opinions on 9 volt alkaline batteries vs. lithium? Lithium last longer and have more power, but I want to make sure I'm not missing anything.
 
I’ve been wondering the same thing. They are also a few grams lighter. I haven’t tested a lithium’s maximum current output but I know fresh alkalines can hit 8 amps for a moment.


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What are your opinions on 9 volt alkaline batteries vs. lithium? Lithium last longer and have more power, but I want to make sure I'm not missing anything.
I am a big believer in Li-ion these days. All my EDC and LEO flashlights are rechargeable Li-ion (CR123A, 18650, etc.) and they are great. You're going to spend more upfront for rechargeable 9v Li-ion but you will save more money and waste in the longrun.
 
I’ve been wondering the same thing. They are also a few grams lighter. I haven’t tested a lithium’s maximum current output but I know fresh alkalines can hit 8 amps for a moment.


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Outputs vary from one Lithium(-ion) battery to the next. If you decide to replace alkaline with lithium, its important to check the replacement has both the appropriate voltage and type/size.
 
Outputs vary from one Lithium(-ion) battery to the next. If you decide to replace alkaline with lithium, its important to check the replacement has both the appropriate voltage and type/size.

I think we were both referring to lithium 9v non rechargeable batteries.


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I forgot to mention, this will be for a Missileworks RRC2+ altimeter. It seems like there was some issue with them using rechargeable batteries.
 
I think we were both referring to lithium 9v non rechargeable batteries.


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Same statement applies if you are referencing Lithium (Non-chargeable) or Li-ion (Chargeable). Either one can have varying outputs.

A 9V alkaline will have six 1.5V alkaline cells inside, while a 9V lithium will have three 3V lithium cells inside. The 3V and 3.6V chemistries are generally not found in the common sizes of AA, AAA, C, or D to avoid accidentally putting one of these higher voltage batteries in a device designed for lower voltages.
 
I forgot to mention, this will be for a Missileworks RRC2+ altimeter. It seems like there was some issue with them using rechargeable batteries.
There should be no difference between Lithium and Li-ion, except one is rechargeable. If a Lithium battery is to high power for the RRC2+ so would the Li-ion. I found the following post from the past but should be relivant.

https://www.rocketryforum.com/showt...for-Missleworks-Altimeter&p=760370#post760370

https://www.rocketryforum.com/showthread.php?128645-Rechargeable-9V-batteries&p=1496767#post1496767
 
Same statement applies if you are referencing Lithium (Non-chargeable) or Li-ion (Chargeable). Either one can have varying outputs.

A 9V alkaline will have six 1.5V alkaline cells inside, while a 9V lithium will have three 3V lithium cells inside. The 3V and 3.6V chemistries are generally not found in the common sizes of AA, AAA, C, or D to avoid accidentally putting one of these higher voltage batteries in a device designed for lower voltages.

I understand all that you have posted. It seems you are telling us that we should ask the question that OP already specifically asked. We are both looking for actual answers. Not recommendations to ask a question.


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I understand all that you have posted. It seems you are telling us that we should ask the question that OP already specifically asked. We are both looking for actual answers. Not recommendations to ask a question.


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His OP stated, "What are your opinions"? There was no question, just asking for a opinion. I stated that I loved Lithium and Li-ion batteries but you must be careful with the varying outputs.
 
I always use a new Duracell 9V. I use them in our smoke detectors afterwards, so I know that I am starting the launch with a fresh one.

Missileworks states on their website that the RRC2 is "optimized for 9V power" - I don't see any reason besides weight saving to go with anything else.


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Lithium batteries (non-rechargeable) operate at low temperatures. Alkaline will have poor characteristics below 40F. Otherwise, the Duracell alkalines are good (welded cells internally, hold up better under acceleration and vibration).

Measure the output voltage of the battery with a 100mA load (100 ohm resistor is close enough) to make sure it's within the spec of the altimeter's minimum recommended voltage.
 
There is a 9V lithium battery that I picked up that actually puts out 9.5 to 9.8V and is recharged off a micro USB socket. I'll post some pictures. I was figuring on using them for some 9V trackers I have.
Some listed 9V lithium size format are a 2S cell which tops out at 8.2 to 8.4V Kurt
 
There is a 9V lithium battery that I picked up that actually puts out 9.5 to 9.8V and is recharged off a micro USB socket. I'll post some pictures. I was figuring on using them for some 9V trackers I have.
Some listed 9V lithium size format are a 2S cell which tops out at 8.2 to 8.4V Kurt

The non-rechargeable are usually 2 cells (8.4V). The rechargeable lithium 9V's can be 2 cells to several cells, depending on the chemistry. There's also a wide difference between the unloaded voltage and the loaded voltage. Load test and verify! Also do the test at the temperature extreme your rocket might see sitting on the pad for a while.
 
The non-rechargeable are usually 2 cells (8.4V). The rechargeable lithium 9V's can be 2 cells to several cells, depending on the chemistry. There's also a wide difference between the unloaded voltage and the loaded voltage. Load test and verify! Also do the test at the temperature extreme your rocket might see sitting on the pad for a while.

It's these John: https://www.banggood.com/ZNTER-S19-9V-400mAh-USB-Rechargeable-9V-Lipo-Battery-p-1070703.htm
They're available all over the place now and I use that site for example only. Like I said, I'd figure I'd use them on some 50mW 2meter
Ham Rdf trackers I got that take 9V. I do have some 8.4V lithiums too that are as you say.

There are also some "True" 9.6V Nimh in 9V format out there but they're 260mah.

If one is flying in extremes of environment, it's probably best to use what everyone else is using since they've already "proven" themselves in the
environment flown. Kurt
 
It's these John: https://www.banggood.com/ZNTER-S19-9V-400mAh-USB-Rechargeable-9V-Lipo-Battery-p-1070703.htm
They're available all over the place now and I use that site for example only.

Broken link.

If one is flying in extremes of environment, it's probably best to use what everyone else is using since they've already "proven" themselves in the
environment flown. Kurt

Don't assume someone else knows what they're doing. ;) I've seen rockets sit on the pad in cold weather, waiting for a window, then come in ballistic. If you don't trust the batteries or altimeter in the cold, put one of those small chemical hand warmers in the altimeter bay (if it fits).
 
Broken link.



Don't assume someone else knows what they're doing. ;) I've seen rockets sit on the pad in cold weather, waiting for a window, then come in ballistic. If you don't trust the batteries or altimeter in the cold, put one of those small chemical hand warmers in the altimeter bay (if it fits).

Ok will try again: https://hobbyking.com/en_us/znter-9...#1&gclid=CInewarR59gCFTeUxQIdKxcPOQ&gclsrc=ds

If one does a detailed search should be able to find them. 400mah.

John, I was implying if a club or group has success with a power source in a particular environment, that would be prudent to try rather than go off half
cocked and fail. Kinda embarrassing when a large group says, "We told you so! As you pickup the pieces of your smashed rocket." This is of course if
you can find the pieces.:wink::cry: Kurt
 
I'd be interested to hear feedback from anyone who has bought and used one of these LiPo 9V batteries. I did not see a C-rating for either. While the mAh ratings looks great, not knowing the amps it can source quickly makes me skeptical.
 
In the product discussions there is this post:

SCHWEIKER0pointsUpdate on 2017-08-30
Note for users: This battery has a permanent running voltage boost converter to make 9V out of a single Li cell. It will fully drain the battery within 6 months even with no use. Secondly, the output voltage is stable until battery runs fully empty, then shuts down. So any external gauge will never show real battery state. Do NEVER run it in any Rx or Tx where safety depends on. You will never be warned before it shuts off.
*******
I run most of my altimeters using 2s LiPo batteries, but keep 9V batteries and connectors handy just in case.
I need to take one of my old AltAcc units on a test ride to see if they run properly on a 2S LiPo battery.

John
 
Ok will try again: https://hobbyking.com/en_us/znter-9...#1&gclid=CInewarR59gCFTeUxQIdKxcPOQ&gclsrc=ds

If one does a detailed search should be able to find them. 400mah.

That's not a battery, it's a power supply: one Lipo cell with a boost converter. No telling how that could fail and fry your electronics. Even under normal operation, you would have to look at the noise/ripple produced by the converter under load. Plus, it has all the problems of charging and maintaining a cheap Lipo cell. You are better off with a standard primary cell battery. Second to that would be a 2-cell Lipo without the internal boost regulator, and keep it maintained with a good Lipo charger.

John, I was implying if a club or group has success with a power source in a particular environment, that would be prudent to try rather than go off half
cocked and fail. Kinda embarrassing when a large group says, "We told you so! As you pickup the pieces of your smashed rocket." This is of course if
you can find the pieces.:wink::cry: Kurt

I recommend that people understand the technology and learn how to test & verify what you're using. It isn't magic or Maxwell's equations! Otherwise, you are copying someone else's problems. "I don't know what happened, it worked ok up until this flight".
 
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So far, I'm not seeing anything that makes me think a 9v lithium is worth the cost (~$10). I'll probably go with Duracell Procells.
 
That's not a battery, it's a power supply: one Lipo cell with a boost converter. No telling how that could fail and fry your electronics. Even under normal operation, you would have to look at the noise/ripple produced by the converter under load. Plus, it has all the problems of charging and maintaining a cheap Lipo cell. You are better off with a standard primary cell battery. Second to that would be a 2-cell Lipo without the internal boost regulator, and keep it maintained with a good Lipo charger.



I recommend that people understand the technology and learn how to test & verify what you're using. It isn't magic or Maxwell's equations! Otherwise, you are copying someone else's problems. "I don't know what happened, it worked ok up until this flight".

Ok, so no good for altimeters. Use duracells. Well heck John, count on somebody trusted to verify. Not everyone has the time to test and verify let alone acquire the stuff to do so.
Right about lipos. They suckee trying to optimize for long life and it's best to get a lipo charger with a storage setting on it. If the battery isn't in the target state for storage, it will either charge it or discharge it to the proper level.
There is nothing out there for these 9V jobs to do that. I'll use my two for toys and 9V radio testing then. Kurt
 
The difference between LiPo batteries and Alkaline or Lithium 9V's is that LiPo battery cells are always welded together whereas only "some" 9V's are. If you pick the wrong battery and the cells disconnect in flight, you're pretty much hosed. Duracell seems to be the consensus if you're going to use 9V's. It matters a lot if you're exposing the battery to high G forces and vibration... just because it works on the ground in testing doesn't mean it will hold up to a VMax flight. Personally, I only use LiPo's, zip tie all the wires down to the sled, and tape the battery connectors together. If it can't move, it can't come loose.
 
I have used these batteries with my PerfectFlite StratoLogger SL100.

https://data.energizer.com/pdfs/l522.pdf

The only problem I had was one of the battery terminals broke off due to a very hard landing. The three internal cells are spot welded together but the battery terminals seem to be press fit.

I have since switched to LIPO batteries due to the very small size of the batteries.

Terry
 
I bought several LiPo batteries and a charger a few years ago. But someone at Missileworks told me they wouldn't work with my RRC2+, and I can't remember why.

180mah.jpg

300mah.jpg

460mah.jpg

1000mah.jpg

charger.jpg
 
Looks like two of those are 3 cell batteries, 11.1 volts. RRC2+ says max 10 volt. The other two are 2 cell and should work fine. I've used 2 cell many times with my RRC2+ with no issues.

Now I need to dissect my 9vs to see if they are welded or not.

Other than (guaranteed) welded cells in the battery, I don't see a benefit of 9v lithium over alkaline, not in our hobby anyway. Rechargeable sure, but no reason to pay more for something that performs the same and still ends up in the trash.
 
All I use the 9V batteries for is running my altimeters which fire ematches. I use Duracell because they have proven durable and last a long time. We fly Oct. to April so they sit in the cold often, I've also had 80G flights and they have always worked fine. I run Perfectflite altimeters which beep out the battery voltage on start up. The altimeters consistently read 0.1 V less then what my meter reads. I ususally don't open the bay and just fly the battery until the altimeter reported voltage is below 8.9V. That is usually 3 years with 6 - 8 flights per year. I suspect they would still work if they were down to 8.0V.

I've had no issues with alkaline batteries and I have no reason to move away from what has been a proven and reliable battery. I don't see any other battery chemistry offering any advantage to how I use the alkaline 9V batteries. I will revisit the battery power/chemistry if I start to use more then just ematches with the altimeters, i.e. air starts or staging.

Just some anecdotal evidence/story. I had a rocket hang in a tree 5 days. Both altimeters were still beeping altitude when it was recovered. The HiAlt45 was down to about 7V and the Stratologger was down to about 5V. With the small draw on the altimeters and low current requirements of the ematches, I don't worry about rockets sitting on the pad waiting during launches.
 
I bought several LiPo batteries and a charger a few years ago. But someone at Missileworks told me they wouldn't work with my RRC2+, and I can't remember why.

Voltage isn't the only concern when it comes to LiPo packs. These batteries can put out 10s of amps and hold their output voltage. The relatively high ESR (i.e. low current capability) of typical 9V alkaline batteries actually works in our favor for altimeter use since they can only source a couple amps or so.

Many altimeters, like the RRC2+, have outputs rated to 5A. You'll never surpass this with an alkaline 9V battery, but you could easily surpass this with a 2S LiPo pack unless you know how to limit the output current driving the e-matches.

Randy
 
All I use the 9V batteries for is running my altimeters which fire ematches. I use Duracell because they have proven durable and last a long time. We fly Oct. to April so they sit in the cold often, I've also had 80G flights and they have always worked fine. I run Perfectflite altimeters which beep out the battery voltage on start up. The altimeters consistently read 0.1 V less then what my meter reads. I ususally don't open the bay and just fly the battery until the altimeter reported voltage is below 8.9V. That is usually 3 years with 6 - 8 flights per year. I suspect they would still work if they were down to 8.0V.

The cold temperature characteristics of an alkaline cell will not show up unless it's under load. Open voltage (or the light load of the altimeter electronics only) will not show the voltage when firing a charge. So, the "beeped out" voltage of the Perfectflite will not show the whole story. Below 40F (cold soaked into the battery, not just ambient) is when the voltage vs temperature tanks for alkalines. Non-rechargeable Lithium-ion cells do much better down to -20F. They also have more capacity in the same 9V size. But all are not created equal, so look at the manufacturer's specs and verify by testing.

Considering the overall cost of the rocket, electronics, and motor, there's no reason to skimp on the battery, or make any assumptions. Duracell alkaline are great for most circumstances (that's what I use). For projects that are going to be outside <50F for a while, I use the 9V Lithiums... and never the Lipo rechargeables in the cold.
 
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