Alternative: A rebuild for Trend Air Pro Battery Pack

[Ryan Baker]

My Trend pro batteries are still going pretty strong (they are starting to lose capacity just a bit at this point). I have always intended to rebuild them just as you did when they get bad enough. Thanks for posting your source.

[Ted Evans]

Really appreciate the info Ken, battery packs are a pet peeve of mine.

[Ken Glass]

Hey All,
I am sure you are bored to death with my posts by now, but I did wanted to give you a final update. The second Battery pack I rebuilt and charged for 12 hours was turned on at 7:15 am yesterday morning and when I shut it off last evening at 7:15 pm, it was still going strong and wasn't even beeping as of yet. That's 12 hours run time. All in all the rebuild seems to be a success and a very inexpensive alternative to buying a new pack.

[kurt sligh]

Hmmm, has anyone been able to create an entire battery pack? I'd like a second battery pack but don't want to buy their's if I can make one from scratch. I just got mine yesterday so I haven't really looked at how the battery pack was constructed.

[dan roscigno]

I know this is an old thread, and I apologize for reviving it

Does anyone have a source for the 70 degree c thermal fuse in the battery pack for the Airshield Pro?

Thanks,
Dan

[Jeffrey J Smith]

Dan: Try Goodman's in Florida or even Radio Shack - they're pretty commonly available at electronics parts outlets. Google is our friend.
Funny you should resurrect this old thread - last weekend I finally rebuilt one of my battery packs from the info that was posted here. I had bought all the parts for two battery packs almost a year ago and put off rebuilding until the batteries were obviously shot.
The rebuild went very smoothly, just mimicking what was done in the original with the new batteries. I reused the old fuse. The new/rebuilt pack seems to work great so far.

[Darryl Hansen]

Ditto on the Trend Customer Service. I would also like to see a tutorial. I believe the one mentioned in another post is for the older style Trend rather than the Pro. One of my packs does give the low voltage warning soon after turning it on but the fan will run for several hours before slowing down.

[Mark Levitski]

I too reused the old fuses when I rebuilt my two Trend batteries last year. I have had great results since then. Way better so far than the original batteries. Thanks Ken.

[Ken Glass]

Hey All,
I am glad everyone is having the same success I enjoyed when I posted this. I turned for 9 hours yesterday and my re-built packs worked well.....I also used the existing fuse for my re-build

[Ray Bell]

Ok, sorry, but I am confused (which isn't unusual) but Ken, is this for the original Trend, or the Airshield Pro? Thank you for posting this.

[Ken Glass]

Ray,
The re-build is for the Trend Pro not the original There are suggested re-builds for the original Trend Air shield in the archives. do a search and you will find them....

[Jim Underwood]

Ever post the tutorial?

[Ken Glass]

Jim,
I haven't because there seems to be a liability issue if I post a pictorial how to, even with this simple re-build. There will alway be someone who wants to sue you for something, just waiting around the bend. It is very straightforward. If you follow the existing wiring and solder all connections the same as the spent batteries are wired, there should be no problems. Remember, to use the same polarity as the existing batteries. The case is easy to open with a screw driver on the tabs and if in doubt, before you start, take a picture or two to be sure. Always be safe and remember I can't endorse this procedure...........but it works the same as the original.

[dan roscigno]

Thanks for the info on the thermal fuse folks (and for the original post, Ken). I will reuse the existing. I am also ordering some, Jeffrey was right, Radio Shack has replacements. The part number is NTE8070. If anyone needs one and does not have a Radio Shack nearby, there is a Radio Shack store that sells through Ebay, with shipping these are under $2.

Regarding polarity, the replacement batteries may not be marked. Look at the tabs, the positive terminal may be covered with a black cover. Also, on both the original batteries and the Tenergy replacement, the positive end of the battery has a white ring like so:
positiveTenergy.jpg

The negative terminal has no white ring:
negativeTenergy.jpg
Using rosin core solder and soldering paste makes things go quickly and helps get a good connection:
solder.jpg

Finally, I bought a Smart Charger:
TenergyCharger.jpg

You may want to buy this first; I have read posts form three people saying that they had "dead" Trend battery packs, bought either this charger or a similar one, used this instead of the charger from Trend, and are happily using the Trend battery pack with no problems.

[Ray Bell]

Ken, thank for the reply. My Airshield is the Pro model, so this works well. I will print this out and use it when I get the second battery pack.