3V battery for door sensor node.
-
Hi,
of course I agree with all comments above. imho 6months, even a year is too short for maintenance..
Regarding frequency, in general, the radio modules run their own crystal so they can't be very impacted on their side by changing 1/8mhz (or maybe spi comm, but that's not the case here, this is usually working).
But MySensors lib "could be". I'm not saying it will!
As changing freq can also change some timeout, delays etc in the lib. So far there is no time slot syncing mechanism, which wouldn't help at all here..
So that may depends on features needed (just thinking to delays in radio drivers for collisions, signing, heartbeat etc when it's about a main door node), and may or not add some nacks, then more transmit, more power etc.. -
@mfalkvidd as long as there is no precise timing involved in lib, this should be ok. who can do more can do less. well this is always good to remember 1mhz mode is not as precise vs 8/16Mhz or faster espressif.
There is another point I'm thinking, when it's about security nodes, lowpower (like a main door node for example). When using 328p deep sleep without time, you lose the watchdog feature. I think, in general, for a reliable security node, wdt may be a good idea to prevent any lockup (especially when using cheap, outofspecs ?? 328p clone??).
Sure it's important to optimize runtime power consumption, but in case of a node which doesn't wake up often, the most important point to improve for lifetime is the sleep power consumption of the device.
I agree with gohan for lifepo4, too bad there are not lot of variants yet.
I think there are no definitive answer for lowpower node and batt lifetime. It depends on the device requirements, always compromise. As a primary lithium AA/AAA+booster will always last a lot longer than a coincell. But that needs nano quiescent current with high efficiency during lightload boosters that you won't find already assembled at aliexpress, +filtering (depends on the part but doesn't hurt)
AA/AAA compromise is a bigger profile than coincell, or need more parts so more expensive for example. Here I guess, a lower profile is needed for a door node. -
@mfalkvidd as long as there is no precise timing involved in lib, this should be ok. who can do more can do less. well this is always good to remember 1mhz mode is not as precise vs 8/16Mhz or faster espressif.
There is another point I'm thinking, when it's about security nodes, lowpower (like a main door node for example). When using 328p deep sleep without time, you lose the watchdog feature. I think, in general, for a reliable security node, wdt may be a good idea to prevent any lockup (especially when using cheap, outofspecs ?? 328p clone??).
Sure it's important to optimize runtime power consumption, but in case of a node which doesn't wake up often, the most important point to improve for lifetime is the sleep power consumption of the device.
I agree with gohan for lifepo4, too bad there are not lot of variants yet.
I think there are no definitive answer for lowpower node and batt lifetime. It depends on the device requirements, always compromise. As a primary lithium AA/AAA+booster will always last a lot longer than a coincell. But that needs nano quiescent current with high efficiency during lightload boosters that you won't find already assembled at aliexpress, +filtering (depends on the part but doesn't hurt)
AA/AAA compromise is a bigger profile than coincell, or need more parts so more expensive for example. Here I guess, a lower profile is needed for a door node.@scalz said in 3V battery for door sensor node.:
But that needs nano quiescent current with high efficiency during lightload boosters that you won't find already assembled at aliexpress, +filtering (depends on the part but doesn't hurt)
Any good suggestion for that ? I'm making a breakout for TPS61098 to test, but if you have other suggestions of similar chips I'm interested :)
-
@gohan said in 3V battery for door sensor node.:
I still believe a 2€ LiFePO4 battery is the cheapest solution :D
Where do you get it at this price ?
-
@gohan said in 3V battery for door sensor node.:
look for soshine AA batteries on aliexpress, I paid 8€ for 4 AA batteries plus 2 connectors
Yes I have those, paid more as shipping was expensive. But they are too big :(
-
@gohan said in 3V battery for door sensor node.:
look for soshine AA batteries on aliexpress, I paid 8€ for 4 AA batteries plus 2 connectors
Yes I have those, paid more as shipping was expensive. But they are too big :(
-
Good topic. I have been lazy since a month to ask the same question regarding best batteries do people use for battery powered nodes ?
I have thought of using AAA batteries but I really do not know which categories do I go with. Lithuim or Alkaline ?
If you check this link https://d2ei442zrkqy2u.cloudfront.net/wp-content/uploads/2016/03/MN2400_US_CT1.pdf
You find that the Alkaline battery can operate till it reaches 1.0 v for more than 1200 service hours. So two in Series will give me 2v which are still above 1.9 for the atmega and nrf to run.
But also if you check lithuim batteries.
http://data.energizer.com/pdfs/l92.pdfIt also operates for 1200 service hours at 1.4v before the battery dies quickly.
My question. Why would I choose a more expensive option (which is Lithuim) although I can use the Alkaline which is much cheaper and may be half the price ? Will the performance is better with steady voltage using lithuim ?
Thanks.
-
Good topic. I have been lazy since a month to ask the same question regarding best batteries do people use for battery powered nodes ?
I have thought of using AAA batteries but I really do not know which categories do I go with. Lithuim or Alkaline ?
If you check this link https://d2ei442zrkqy2u.cloudfront.net/wp-content/uploads/2016/03/MN2400_US_CT1.pdf
You find that the Alkaline battery can operate till it reaches 1.0 v for more than 1200 service hours. So two in Series will give me 2v which are still above 1.9 for the atmega and nrf to run.
But also if you check lithuim batteries.
http://data.energizer.com/pdfs/l92.pdfIt also operates for 1200 service hours at 1.4v before the battery dies quickly.
My question. Why would I choose a more expensive option (which is Lithuim) although I can use the Alkaline which is much cheaper and may be half the price ? Will the performance is better with steady voltage using lithuim ?
Thanks.
@ahmedadelhosni with most low-power nodes, we're talking >10,000 service hours. With those low drains, the self discharge of the battery becomes much more important than how much they can deliver at 1mA drain. Unfortunately, neither of the datasheets you link to contain self discharge. I don't know why they don't include it. The ENERGIZER L92 specified a shelf life of 20 years though.
https://en.wikipedia.org/wiki/Self-discharge#Typical_self-discharge_by_battery_type lists typical self discharge for some battery types though. Lithium-metal is better than alkaline batteries, which is better than (rechargeable) Lithium-ion which is better than (rechargeable) NiMh.
In short, yes it is probably better to choose a Lithium battery because the alkaline battery will have self-discharged after ~5 years while the Lithium battery can go 10 (or more).
-
In addition to what @mfalkvidd said, when you use nrf24, the lower the voltage the lower the emitting power, so the quality of your radio link can decrease and you can lose messages, meaning your sensor could appear unreliable or have to resend the message a lot a lot meaning shorter battery life.
But if you have a really low power node you will have a very long battery life (2-3+ years) with standard AAA so I would go for a good quality alcaline (not a cheap one to avoid leaks ruining your sensors). And if you see you have range problems when voltage goes lower then switch to lithium version.
-
@scalz said in 3V battery for door sensor node.:
But that needs nano quiescent current with high efficiency during lightload boosters that you won't find already assembled at aliexpress, +filtering (depends on the part but doesn't hurt)
Any good suggestion for that ? I'm making a breakout for TPS61098 to test, but if you have other suggestions of similar chips I'm interested :)
Any good suggestion for that ? I'm making a breakout for TPS61098 to test, but if you have other suggestions of similar chips I'm interested :)
I was thinking to these boosters. They are nice, I used them in a old multisensors project I showed here.
Hmm.. it's not at all handsolderable, what happens ?! :stuck_out_tongue_winking_eye:
I'm kidding ;) I'm the same, I don't like to be limited by parts choice.This booster is very small, but 6 pins only if i remember. better use good parts, good shielded inductor, good planes etc to reduce emi, improve efficiency etc.
I moved to different battery types because I wanted more discrete nodes, or simplicity, and between AA/AAA there is not a big profile difference. But I still have a recent design with this booster, for a usecase. -
Any good suggestion for that ? I'm making a breakout for TPS61098 to test, but if you have other suggestions of similar chips I'm interested :)
I was thinking to these boosters. They are nice, I used them in a old multisensors project I showed here.
Hmm.. it's not at all handsolderable, what happens ?! :stuck_out_tongue_winking_eye:
I'm kidding ;) I'm the same, I don't like to be limited by parts choice.This booster is very small, but 6 pins only if i remember. better use good parts, good shielded inductor, good planes etc to reduce emi, improve efficiency etc.
I moved to different battery types because I wanted more discrete nodes, or simplicity, and between AA/AAA there is not a big profile difference. But I still have a recent design with this booster, for a usecase. -
@gohan
yes these one; I have different variants but the family is TPS6109x.
I made a multisensor two years ago with this booster (published a preview in the forum). works well, but finally I published an other multisensor, which was cheaper, on coincell. But still not enough cheap for people ;)
Now I prefer to have just a few projects&revisions, than too much. to save time and support. So I carefully sort my stuff :) -
Any good suggestion for that ? I'm making a breakout for TPS61098 to test, but if you have other suggestions of similar chips I'm interested :)
I was thinking to these boosters. They are nice, I used them in a old multisensors project I showed here.
Hmm.. it's not at all handsolderable, what happens ?! :stuck_out_tongue_winking_eye:
I'm kidding ;) I'm the same, I don't like to be limited by parts choice.This booster is very small, but 6 pins only if i remember. better use good parts, good shielded inductor, good planes etc to reduce emi, improve efficiency etc.
I moved to different battery types because I wanted more discrete nodes, or simplicity, and between AA/AAA there is not a big profile difference. But I still have a recent design with this booster, for a usecase.@scalz said in 3V battery for door sensor node.:
This booster is very small, but 6 pins only if i remember. better use good parts, good shielded inductor, good planes etc to reduce emi, improve efficiency etc.
Yes I sticked to what is suggested in the datasheet and bought everything from arrow. But in the end it takes more space than expected so I'm not sure I'll make the board...
-
@scalz said in 3V battery for door sensor node.:
This booster is very small, but 6 pins only if i remember. better use good parts, good shielded inductor, good planes etc to reduce emi, improve efficiency etc.
Yes I sticked to what is suggested in the datasheet and bought everything from arrow. But in the end it takes more space than expected so I'm not sure I'll make the board...
@nca78 said in 3V battery for door sensor node.:
Yes I sticked to what is suggested in the datasheet and bought everything from arrow. But in the end it takes more space than expected so I'm not sure I'll make the board...
yep it was another point i forgot to mention..
