Anyone know much about toll transponder batteries

[y_p_w]

I figure since there's been talk about lithium batteries, maybe someone knew more about these toll transponder batteries. I've been using California's FasTrak system for over a decade, but it always annoyed me that if the battery is depleted the only solution is to return it and get a replacement with a fresh battery. As far as I can tell they actually replace the batteries and reissue old transponders. I had a replacement that looked a bit discolored and scratched, but it worked fine.

I heard they used "lithium" batteries and had a nominal 5 year life, although it obviously will vary. This is kind of a tough environment since it can get really hot inside a car, where at minimum it will reduce battery life and worst case will leak. But for a rated 5 year life I thought it had to be something like a CR2 or CR123. I finally had a look at what's in an earlier Bay Area FasTrak transponder, and it's a Panasonic BR2477A 3V lithium cell. Apparently a tabbed cell that's bigger than a coin cell but smaller than a cylindrical cell. About 1000 mAh and designed for higher temperature operation/storage.



Anyone played around with one of these things before? I suppose most people won't because there's a deposit or at least they'll make the customer pay for one that's damaged. But it occurred to me that Costco sells them locally with a discount compared to the toll value and no deposit, so someone could buy one of them, use up the toll value, then disassemble.

I know of one version of these in California that had a battery hatch (with test button) and is user serviceable with a CR2450 battery. I mean - that means the customer is expected to pay for it compared to a free replacement, but it's a big pain to either mail one in and wait for the replacement or go to a service center.

 

[Leo99]

My transponders must be 15 years old

 

[blupupher]

RFID for the win.

Or just photo of the tags and charge it to the account.

 

[y_p_w]

Originally Posted by blupupher
RFID for the win.

Or just photo of the tags and charge it to the account.

Who uses passive RFID over an active battery powered transponder other than SunPass?

 

[eljefino]

Originally Posted by blupupher
RFID for the win.

Or just photo of the tags and charge it to the account.



RFID doesn't work well past a couple inches. Are you sure you don't have a battery in yours? EZPass has batteries too.

 

[blupupher]

Around here you just put a sticker on your windshield, no battery in it.
RFID can have a longer range if designed to do so.
These have been in use down here for at least 10-12 years.

FROM THIS SITE

I had no idea that there were still battery powered transponders in regular use.
I know for motorcycles or certain coated windshields they are used, but for regular vehicles, all the toll agencies around here use stickers.
You also have the option of registering your license plate with a toll company, and it uses just that for tolls (I heard it does not work on some of the tollways, but all the ones around me it does). My motorcycle and Santa Fe do not have any toll tag on them, but my account gets charged for their use by the plates (usually takes a day or two to show up).

 

[BeerCan]

Originally Posted by eljefino
Originally Posted by blupupher
RFID for the win.

Or just photo of the tags and charge it to the account.



RFID doesn't work well past a couple inches. Are you sure you don't have a battery in yours? EZPass has batteries too.


Edit: my brain is not working because I have not had enough coffee. I read ezpass but saw sunpass.

sunpass transponders have not had batteries for a few years now. Most of them are the sticker type. I have one that is bigger, I'll see if I can pop it open but I know it does not contain a battery.

 

[Vikas]

EZpass system keeps track of the transponder battery age. The system sends you new transponder when it deems that the battery is beyond its service limit. I think this happens every 5 years or so. My experience is with NJ EZpass. Those transponders do not have user serviceable battery compartment. You get the new transponder and you send the old one back.

 

[y_p_w]

Wasn't sure about the RFID type. I remember thinking of going on vacation in Florida and researching how to pay tolls. My last visit to Florida there were still cash toll lanes, including the kind where coins drop into a chute. It seemed kind of odd paying a toll with a single quarter though.

I was under the impression that the RFID sticker type only worked because it was pressed directly onto the windshield glass, and that taping it to the windshield probably won't work. I thought that they were specifically engineered to work that way, but where it won't work if not directly against the glass. And of course they warn against certain complex windshields where they recommend a license plate mounted tag.

 

[BeerCan]

In FL there are very few cash lanes left. They also have suction cup type transponders that use rfid. It is the kind I use or they take a picture of your plate and bill by mail

 

[nthach]

The FasTrak transponders use some weird Tadiran lithium thionyl battery that's designed for extreme ambient heat and stability. I know TransCore makes them - seeing how they provide the ETC systems for Caltrans/BATA. I question the lifespan of them, the longest I've had a FasTrak transponder last was 4 years. My current one is DOA and I need to get a new one.

http://www.tadiranbat.com/toll-tags.html

 

[y_p_w]

Originally Posted by nthach
The FasTrak transponders use some weird Tadiran lithium thionyl battery that's designed for extreme ambient heat and stability. I know TransCore makes them - seeing how they provide the ETC systems for Caltrans/BATA. I question the lifespan of them, the longest I've had a FasTrak transponder last was 4 years. My current one is DOA and I need to get a new one.

http://www.tadiranbat.com/toll-tags.html

That might be it these days, or maybe multiple suppliers. They're still reissuing many of their older versions since they still work with new batteries. I think the teardown of that Bay Area FasTrak transponder (with the Panasonic BR2477A) was for an old one. However, the BR2477A is described as "Coin type lithium batteries for high temperature".

Quote
https://industrial.panasonic.com/ww...m-batteries-high-temperature-bra/BR2477A
Nominal Voltage (V) 3
Nominal Capacity (mAh) 1000
Continuous Standard Drain (mA) 0.03
Diameter (mm) 24.5
Thickness (mm) -
Height (mm) 7.7
Approx. Weight (g) 8
JIS -
IEC -
Operating temperature(degree C) -40 to 125

My parents had one that was completely dead, but they still got tracked using their license plate. I told my dad to go to the FasTrak office in San Francisco to pick up one of the new "Flex" ones for the HOV lanes that require these to avoid paying tolls as an express lane. They probably have a variety, but the ones I got were their new slim ones.

Here's some video of a guy who broke his Metro Express Lanes FasTrak transponder, but noted that he could get it to work by pressing on the battery. The battery looks like the image from the site that you linked.

 

[DBMaster]

My NTTA (North Texas Tollway Authority) TollTag is like blupupher's sticker. NTTA was supposedly the first tolling authority in the U.S. to use the tags. I had an older, hard cased tag for years, but a couple of years ago NTTA phased them out completely and required everyone to replace them with the stickers. No batteries were ever used in them as far as I know. They want to make it as easy as possible to collect those extra "taxes." Since Texas hasn't raised fuel taxes since 1991 this is the way new highways are funded around here. I don't like the way the stickers look so I stuck mine to a thin piece of closed cell black craft foam and stuck it down between the dashboard and windshield. It's nearly invisible and works just fine - my credit card can vouch for that.

 

[JTK]

Interesting! I never really thought about batteries in these. I've had EZpass for 23+ years and use them most days of the month. Only one time that in all those years I can recall they sent me new transponders.

 

[y_p_w]

Originally Posted by JTK
Interesting! I never really thought about batteries in these. I've had EZpass for 23+ years and use them most days of the month. Only one time that in all those years I can recall they sent me new transponders.

The deal is that they're used far more than just for tolls. Most systems actually talk to them at certain points, which are then used to monitor traffic patterns. The data is supposed to be assigned to special tracking numbers where they only store those numbers for archival purposes, and the key to match a record to a particular toll tag is discarded at the end of the day. However, this means the transponder is communicating quite often if you don't have it shielded.

https://gizmodo.com/e-zpass-is-the-best-tracking-device-thats-already-in-y-1308535900

 

[nthach]

Originally Posted by y_p_w
Originally Posted by JTK
Interesting! I never really thought about batteries in these. I've had EZpass for 23+ years and use them most days of the month. Only one time that in all those years I can recall they sent me new transponders.

The deal is that they're used far more than just for tolls. Most systems actually talk to them at certain points, which are then used to monitor traffic patterns. The data is supposed to be assigned to special tracking numbers where they only store those numbers for archival purposes, and the key to match a record to a particular toll tag is discarded at the end of the day. However, this means the transponder is communicating quite often if you don't have it shielded.

https://gizmodo.com/e-zpass-is-the-best-tracking-device-thats-already-in-y-1308535900

You forgot parking, well at SFO at least. Not at OAK or SJC.