Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

What type of battery to apply (rechargeable, low temp, long time)

Status
Not open for further replies.
V

Vladymir

Newbie level 5
Joined
Jul 1, 2017
Messages
8
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
67
Hello
I'm going to build a wireless weather sensor powered by micro solar panel (5.5V 1W).
What type of battery will survive long winter months with very low temperature and could be charge with no limits?
I was considering to use a LiFePO4 battery.
Do you have better ideas?
Regards!
 

Hi,

Could you specify "very low temperature"?
And what amount of energy need to be stored?

I tend to a gold-cap.
Low temperature, no aging.

Klaus
 

Up to 1000mAh and -25 C (-13 F)
 

Hi,

This is no energy. Either you give the energy, or additionally the voltage.
Why that much Ah? Can't you design it with less power consumption?
Is this value an assumption, or calculated?

What type of battery will survive long winter months with very low temperature
Click to expand...
Just survive, or should it operate during this time?

* a battery uses a chemical process, which is slow at cold temperatures, this decreases the usable energy and increases internal impedance. But it may survive those cold temperatures.
* a goldcap uses a physical effect, therefore it doesn't suffer from those drawbacks.

Klaus
 

Baterry should operate below -20 C (-4 F).
What do you think to apply LiFePO4 battery?
*EDIT* 1000mAh and 3,3V
 
Last edited:

Vladymir said:
1000mAh and 3,3V
Click to expand...

That turns out about 3.3AH= 12000J

Do you really mean that the surface temp of the battery will be around -20C? Do you plan it to work over the whole winter (six month)?

Honestly speaking, whatever you may have in mind, you will find it easier to have insulation about the whole electronics box to keep it around 0C.

Even a three layer Thermos flask may be a cheaper alternative. Even with the Gold Cap alternative, you may be better with a Dewar flask having all the electronics.
 

Surface temp of battery will be around -20C only at most 20 days in year.
1000mAh is a litle bit overestimated value but with a margin.
Solar panel during avarage radiation delivers enough energy to run the sensor during all twenty four hours but i assume bad weather for two weeks.
 

I was considering to use a LiFePO4 battery.
Click to expand...

All electrochemical cells ("batteries") become useless if the electrolyte freezes; once dead it does not come back to life. I guess most common Zn-based cells use aqueous electrolyte and they will surely die at -20C.

The Li-cells use organic electrolyte but I do not know whether it will freeze at -20C. Will be solute precipitate out?

Whatever battery you may use, it can deliver at most 10% of the rated capacity at -20C (derate capacity by 50% for 10C dec in temp).
 

I have a remote outdoor thermometer which sends readings to an indoor base. I live in Minnesota where winter gets below -10 F. Two AA alkaline is the only battery type recommended in the instructions. They last through a winter.

I believe I remember trying nicad or nimh. They worked for a brief time after a recharge but even then a cell is nominally 1.2V. Extreme cold caused voltage to drop even lower. Moreover the cells self-discharged more quickly in the cold. I decided rechargeables are not worth the trouble.
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top