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Backup batteries

Captain_John

Captain_John

Well Known Member
Hey All,

I am installing my IBBS Backup Battery as I type this.

...also Machine Man is a tad over 2 years runtime into his RV-7 with the same G3X panel as mine.

His IBBS just went Tango Uniform. It won't boot the system for startup without invoking the Odyssey.

Now, I went and broke the seal on my IBBS and was underwhelmed at the puny batteries within.

I like the "brains" if you will, of the IBBS. It seems like a good design. Besides, he is already wired for the IBBS.

Here is my thought...

Rather than sending the unit back to have it refurbished with the same puny cells, how bad would it be to bring the battery leads out of the box and wire them to an AGM alarm battery? Perhaps something in the vicinity of a couple of ampere hours?

The IBBS advertises it to be 4ah, but I seriously question that.

Mikey, you rolled your own alarm battery setup. How is that working?

Anyone have an opinion on what I am proposing here?

:cool: CJ
 
SeeJay-

I went BIG on my aux battery - 9 Amp-hour (PowerSonic PS-1920 F2 - $24)

IMG_9640.JPG


I isolated it from my main bus with a schottky diode (IXYS 45V 2X59A, about $21.09 at Mouser.com).

IMG_9641.JPG


Before I start my preflight check I flip on my Aux Battery Bus which powers essential items (GRT EFIS's and Garmin 430W) to make sure the aux battery still has some juice left in it. Every annual I run it down. I am amazed I get over an hour!

Total cost is less than $50, and replacement batteries can be had anywhere. Plus you get over double the runtime than the overpriced $375 IBBS. My system has been going strong for 3 years now without an issue.


You could always go smaller. Power-Sonic has a good battery selector guide here:
http://www.power-sonic.com/ps_psg_series.php
 
My IBBS has not been used yet, but I did need to take the back off (I love to see inside black boxes) and the batteries are indeed small. I did not take pictures, but guess the batteries are not much of the cost. Since they are LiO batteries, then a good management system is needed. It appears to be there. If one were to be thrifty, why not just replace the internal batteries on your own?

They appear to be sub-c size and there are plentiful options. Maybe even the local battery shop that make custom repairs to hand tool battery packs.

Be careful about just wiring in a different battery chemistry, esp.
lead acid (PbA)

Sorry, they are NiMh batteries.
 
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CJ,

I could not force myself to spend the extra $$$ on the IBBS. I did just like Mike and rolled my own backup.

I did a 7.5Ah battery that is exactly the same size as the one in Mike's pic. When I replace it, I am going with the 9.0Ah one.

When I start up, I flip on the Backup Battery Bus and this powers the essentials which are the PFD1, MFD, GSU73 and the Dynon D6. This bus remains on till shutdown. This keeps power on the backup power inputs to those items and prevents brownouts during startup.

The backup battery is charged anytime the master is on and I have a current limiting resistor (some don't use one) and a Schottky diode for isolation.

I get about an hour of runtime with this setup.

Cheap and effective! Easy to find and replace batteries used in millions of UPS's and alarms all over the world.


As far as using the IBBS guts to charge and manage a different battery, that would depend on what kind of charger circuit is in there.
 
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I made a custom craddle for mine out of 3/4" angle from Home Depot Aircraft supply. It is bolted on the fwd side of the subpanel right where the filler plate is that covers the hole that was in the subpanel for the original map box that I removed.
 
My craddle looks similar to Mike's just out of 3/4" x 3/4" x 1/16" angle and not as long since mine is mounted with the side of the craddle instead of the bottom.
 
Battery charging

Thanks to Brian here and Bill Peyton for the ideas, I did similar but used a Shoria battery as backup and sterling power battery charger/maintainer. It is designed as complete secondary system with no connection to to main battery or primary buss/vpx. The only connection is this product which takes Brian and Bills ideas and combines them with off shelf component. Limits charging to backup bat to 3amps/ diode protects, and does not transfer power till primary reaches 13.3 volts. Over voltage protection and fuse protected on in and out wiring all in one package.
http://www.shop.sterling-power.com/acatalog/Battery_Maintainers.html
Can post a picture if interested. I am not flying but have tested the electrical system and it works as advertised.
Only issue is the Sterling unit has indicator lights which would be nice to see.....remote camera mounted behind bulkhead wired into our new AFS 5400?
 
bullojm1 said:
SeeJay-

I went BIG on my aux battery - 9 Amp-hour (PowerSonic PS-1920 F2 - $24)

IMG_9640.JPG


I isolated it from my main bus with a schottky diode (IXYS 45V 2X59A, about $21.09 at Mouser.com).

IMG_9641.JPG


Before I start my preflight check I flip on my Aux Battery Bus which powers essential items (GRT EFIS's and Garmin 430W) to make sure the aux battery still has some juice left in it. Every annual I run it down. I am amazed I get over an hour!

Total cost is less than $50, and replacement batteries can be had anywhere. Plus you get over double the runtime than the overpriced $375 IBBS. My system has been going strong for 3 years now without an issue.

You could always go smaller. Power-Sonic has a good battery selector guide here:
http://www.power-sonic.com/ps_psg_series.php
Click to expand...

Ditto. That is exactly what I did. Except. . . A model nose roller with a constant speed prop, I mounted mine behind the baggage bulkhead. (fused at the battery).
 
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bullojm1 said:
I mounted mine between the subpanel and firewall. I made a bracket out of leftover longeron material.
Click to expand...
Thanks for the pics, Mike! Any issues dropping the battery for maintenance/replacement? If not, I may blatantly steal your design...:)

Dave
 
Thermos said:
Thanks for the pics, Mike! Any issues dropping the battery for maintenance/replacement? If not, I may blatantly steal your design...:)
Click to expand...

No issues whatsoever! I made sure to run my wires around it in such a manner I could remove it easily. Just keep this in mind when wiring up everything.
 
bullojm1 said:
SeeJay-

I went BIG on my aux battery - 9 Amp-hour (PowerSonic PS-1920 F2 - $24)
<snip>

I isolated it from my main bus with a schottky diode (IXYS 45V 2X59A, about $21.09 at Mouser.com).


Before I start my preflight check I flip on my Aux Battery Bus which powers essential items (GRT EFIS's and Garmin 430W) to make sure the aux battery still has some juice left in it. Every annual I run it down. I am amazed I get over an hour!
<snip>
Click to expand...

<snip> I start up, I flip on the Backup Battery Bus and this powers the essentials which are the PFD1, MFD, GSU73 and the Dynon D6. This bus remains on till shutdown. This keeps power on the backup power inputs to those items and prevents brownouts during startup.

The backup battery is charged anytime the master is on and I have a current limiting resistor (some don't use one) and a Schottky diode for isolation.

I get about an hour of runtime with this setup.

<snip>
Click to expand...

Brian/Mike,

This is exactly the setup I'm looking to implement. Just a little hazy on the details/operation. It appears you have the same configuration.

Do you have an electrical diagram of this setup? I'm assuming you have a 3 way master switch for (off) - (main) - (backup)? I like the idea of charging both the main and backup battery simultaneously. Unfortunately, I have to equate diodes to check valves so my mechanical mind can understand what's going on. I am not sure why your diodes have 4 terminals on them, and what they all go to. Also, I am sure you can't just hook up both batteries to the alternator output. You need to limit the current somehow, with a resistor?

Anyhow, if you guys have the information handy it would be extremely helpful.

Thanks!
Chris
 
Chris.
I suggest two switches...one for master one for backup. We used ztron solid state relay for backup circuit enable.
As far as charging and separation ect look at post 9. Working very well for us and off shelf component that covers multiple functions. Backup battery will charge as soon as primary reaches 13.3 volts and is 3 amp current limiting, over voltage protection, uni directional( diode)
 
Chris,

Here is my circuit:

http://www.vansairforce.com/community/showpost.php?p=725276&postcount=72

You can use a switch like you proposed or two switches. I have two, one for master and one for the backup bus. If you only use one, think about how you want it to work. B&C sell switches that can do all sorts of tricks.

The reason that diode of Mike's has four terminals is because that block has multiple diodes in it.

PS, I really like the looks of the device Jack refers to above!
 
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In looking at the IBBS, it looks very similar to "roll your own" solution I created. The "brains" - if you can call it that, is - is the simple charging circuit. With this circuit you can use most any battery you like. I went with an 18AH LiFePO4 (overkill I now know).

 
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CJ,

Hope I didn't steal your thunder but I think we're after the same thing here.

Thanks everybody for the suggestions, that helps clear it up quite a bit! I just couldn't fork $400 for a low capacity backup battery, despite the appealing nature of an all-in-one black box approach.

Brian, thanks for posting the link again. I knew I had seen it somewhere before, just couldn't find it. Looks like I'll be doing something like the three solutions posted above... although Glen soldering is not my strong suit so I'll likely go for crimped terminations.

The only concern now is all the "problems" with battery charger and battery compatibility (e.g. this link). Maybe it's easier and cheaper just to replace the backup battery every year or charge it externally. But thanks guys for the quick responses. I'll post my electrical lineup when it's finalized.
 
Please forgive my ignorance if you will. A couple of questions.

IBBS? Integrated/internal Battery Backup System?
Are you guys making these in leu of the manufacturers backup systems?
Does it depend on the manufacturer on whether the batteries are internal to the unit? I guess I assumed it would be an extra box with it.

Thanks
Mark
 
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