Emergency Apocalypse Cell Phone BATTERY EXTENDED X4





Introduction: Emergency Apocalypse Cell Phone BATTERY EXTENDED X4

We all know that the biggest problem after being affected by a natural disaster or a Zombie Apocalypse , is loss of the electric grid. And all phones specially new ones have short battery life of 8h if we are realistic. All cellphone towers have backup generators or battery banks enabling them to work of grid 48h or more and would be on priority list to get grid power back. So here is my creation a cellphone for survival you charge it and put is in your bug out bag and you are prepared. This cellphone has got 52days stand by and 12h of talk time . This is an old reliable Nokia 3510i from the good old days when phones didnt brake down :) it has a factory 1100mah battery and what i did is added 4 new 1100mah batterys on the back and increase the battery life by factor of 3.

Step 1: Geting a Phone and Batterys

I had chosen a old Nokia since they are reliable and dont use much battery as new ones, you can use and phone just pick one with most standby time Gsmarena.com for reference. I had some of old battery s laying around you can buy new ones if you want but i measured this ones they had 90% capacity left so i used them.You pick what best for your phone to fit on it:)

Step 2: Preping the Batterys

Prepping your battery's they all have 3 or 4 more pins my had 3 so i applied solder on the plus and minus the middle pin is not used so no need. Dont worry batt wont explode when exposed to your soldering iron .

Step 3: Conecting the Batterys

Solder your connections so plus of each is connected to plus and minus to minus . We are paralleling all the batterys s we keep the same voltage and increasing the capacity.

Step 4: Mounting the Batterys

I dried a hole on the back of my case so i can put the my cables thru . After fitting it and i put some electrician tape to isolate the connections so they dont short out . I mounted my battery's temporally with tape and then used hot glue to make a more permanent .

Step 5: CoNeCtInG the Bat to the Phone

Ok now it gets interesting , since my original bat what old typ 4 pin . I had to open the old bat and ant take the protection board . Some phones will not power with out this board since the middle pins send temp of the battery to the phone for protection . Tip ( if you don't have the old bat , connecting a 100k resistor between the two middle pins will fool the phone and it will power on )

After taking the board out put wire on the board and connect it to your cell

Step 6: You Are Ready

After connecting the wire i made a small change i could not get the wires to get in the battery compartment when i put the battery cower. So i took the wire from the battery and soldered them to the pcb i took out of the old battery . I pureed hot glue on all the connection places to secure them and prevent mechanical and electrical damage.

Step 7: Congratulation You Are Ready for Anything

I hope you find this interesting post any questions and i will answer you.



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    I would much rather go with a satellite phone. If there was an apocalypse, than power would probably be lost. No power, no cell towers, no phone service. Whereas the satellite phone on the other hand, as long as the satellites are in orbit, and you are not in a very heavy metallized building, you should be fine. You will probably have to wait a bit for it to connect to satellites whenever you get a connection, you will most likely not have many problems placing a call.

    Could it have been possible to just make them hot swappable?
    With that in mind, I would suggest a small magazine to hold the batteries with the phone and two points in which, for a moment, you could place a charged cell in and remove the low cell.

    I have connected 2 wires(0.25mm²) to the contacts of the cellphone, the original battery stays there and gives the original charger something to work on, it also makes the extra two 18650 pack hot swappable. Don't worry it will not explode when you put a fully charged 4.20V 18650Pack(2 parallel even old ones will easily deliver 10Amp short circuit) parallel to the empty 3.3V internal battery. The electronic fuse of the original battery will protect it, when you have such a low resistance for the 0.9V difference Voltage of the batteries, which is not so easy as you will think.
    The bigger problem are the connectors, I was lucky to have single gold plated male/female contacts from Sub-D connector building sets, very small with low resistance.
    But don’t worry about the battery life, or do your cell towers have emergency batteries/generators for more then 4 days?

    It would be possible to make them hot swap but , no use since the phone is using all the battery all the time so when they are low they are all low . I could make a small pcb and fit it in the case with a connector for 9V battery so when your battery get low you could plug a 9V cell for extra ruining time .?

    never connect batteries in parallel, they will charge/decharge each other. you will lose a lot of capacity, and they will get broken very soon!

    Yes and No they will do that but at a small level and that will stop after a few cycles.And paralleling battery's is a common practice Electric cars ,planes and so on . The main thing is that the battery are the same or capacity if they were not then we would have a problem.On my build every battery has got they own bms so they will all get fully charged .

    But parallel batteries in any commercial product are at least from the same batch, in any high reliable electronics (such as planes) they will likely have matched capacity. You however picked

    some of old battery s laying around

    and I highly doubt these will work as reliable as commercial battery packs. And after all reliability is the number 1 priority when designing any emergency gear.

    Yes but i think the 10% loses are not inportant in this aplication

    It's not about the loss, it's about the current flowing into each battery. If they are slightly different (batch, age, nuber of charging cycles) they will deliver (or drain) a different current at the same voltage fixed voltage, which rapidly speeds up the aging process.

    On the other hand the load stays the same as before, so at least they won't create more heat then the sigle cell. Thus the risk of fire or explosion is as low as before.

    There is no point in beeing anxious about "strong" and "weak" cells in parallel.
    This happens all the time in aging laptop-batteries. There are at least 2 18650 li-ion cells in parallel even 3 in some cases. And one of them will age prematurely, no safety hazard at all. And aging occures not only as capacity loss, but foremost as increasing inner resistance. So the main current will flow through the "better" cell. When you use a standard weak charger there will be no problem at all.
    I use two 18650 cells in parallel at my old cellphone. I set my lab power supply to 4.20V the current limiter keeps it below 2.5Amps, that is below 1C for one cell. I only use scavenged cells from old laptop batterys "fresh"from the recycling bin(in germany at every super market) so for the first time I will put my fingers every minute or so on the cells. If they get warm I will discard them.