Fitting mobility 12volt AGM battery.

I'm the same way... The latest tech at the convention for these types of 12volt batteries is using a capacitor, sensors and phone app to maximize lifespan. It's being done by a company that makes high end security alarm systems and needs the batteries to last for many decades, but maybe in the future we'll have similar options and the 12v battery will be good for the lifespan of the vehicle....

 

I've read through all 19 pages of this thread, and I've learned quite a bit along the way. Thanks, everyone, for your contributions.

My car's second OEM 12v battery is on its last legs, and I've been wondering about replacement options for a while now. Just my luck to stumble upon this thread...

So from my understanding, this battery would be a good option for my California almost-daily-driven 2008 w/ SKS...
https://amzn.to/2FBF3cJ

It does not appear to have a dedicated vent hose attachment point, but by my understanding the consensus is that that should not be necessary, seeing as these batteries are commonly used in indoor applications regardless of external venting capability.

I am fine with modifying the battery clamps and the battery hold-down - is there anything else I'm forgetting??

Cheers

 

Not forgetting anything, just spending $55 more than is necessary.

12350 battery | eBay

 

Go with the 12550 12v 55ah.

 

That's 35ah not 55ah.

 

I know it's 35amp, been working over 4 years for me in my 190,000 mile 2010.

 

Almost one year in, I think my mobility battery may be starting to fail. I took my Prius for its checkup yesterday, and the battery tested low, by "cold cranking amps." By my multimeter, it tested at 11.9 V with the hatch open (which does create some load). I charged it with a trickle charger to the point where the charger read "full" and it went up to 12.3 V. No symptoms at all, and it's been cold here -- just barely above freezing. Last winter the original battery read below 10V and was causing the car to behave strangely.

Here is my original post: Fitting mobility 12volt AGM battery. | Page 17 | PriusChat

Advice is welcome if anyone feels so inclined. My plan is to keep it on a trickle charger at home and keep an eye on it.

 

Perhaps plan to use overnight 12v auto trickle charger to keep it warm on the coldest nights of the year, though that's probably not too much of an issue.
As far as I know this thread has yet to discuss mobility battery limits in freezing temps.

 

$120 amazon battery vs $152 Bosch at PepBoys: $32 difference

$152 direct drop in replacement 12V AGM battery from Bosch available at PepBoys.

• JIS terminals; no terminal modification needed, reuse OEM terminals
  
• vent tube port; reuse OEM battery vent tube
• reuse hold down tie
  
• 4 year straight warranty, no proration
• 3 year free roadside JUMPSTART assistance included
• S6 AGM Car Battery | Bosch Auto Parts

 

That's a better price and more Amp hours than what most auto parts stores sell for Prius, but it's still $24 more expensive and 10 less amp-hours than the Batteries Plus Mobility/Computer Back-up power supply 12v...

Also shipping Bosch batteries from Europe is done in much lower quantities, with much lower demand so they take longer to sell and you risk getting stuck with an older battery that's been sitting on a shelf for a while.

The Batteries Plus Battery, which I got for a friend's car last June $125 came off the pallet it was shipped in on that morning because he said they sell so many of 'em they don't really have much time to put 'em away because they head out the door so fast: Duracell Ultra 12V 55AH AGM SLA Battery with M6 Terminals SLAA12-55C/FR 1 $125.99

 

Last winter we had several nights with single-digit Fahrenheit temperatures, and it never failed to start. But the cold might be causing excess wear or simply causing the voltage to read low. It's supposed to get up into the 70's this weekend, so I plan to test it then to see if it makes a difference.

 

I read a Tesla article today about how the cold weather update can be used to preheat the inside of car and thus the batteries while car is still charging to reduce degraded battery range in cold weather. Similarly you could use Prolong charging system on Hybrid battery and a trickle charger on 12v battery and then use a remote start to warm the car up for 10 minutes before you head out to improve MPG... But if you did that you'd be a total Prius nerd and who wants to be that? Besides it'll just lead to you spending $2k on a new battery pack before the old one dies.

 

The Prius has been setting for three of four days and during last night, the wife noticed an orange glow outside. She went out and the left turn signal was on but not flashing, the dome light was on. She turned the dome light off, but couldn't get the left turn to go off. I went out this morning and hooked a good battery to the jump point and got the hatch open. The 12v was only showing 5 volts and I could try to get the car in ready but it gave me a message about the park not operating and to apply the e brake, the left turn light were still lit and not blinking. I disconnected the 12v in the rear and hooked a good battery to the cables there and all is fixed, no lights on and the car booted up as normal. The $64.99 mobility only lasted 4yrs and 2months, so I ordered another $64.99 mobility to replace it and see if it lasts another 4yrs.

 

Milkman, do you remember what brand of battery you bought that lasted that long?

 

Update: at 56 deg F, and with the hatch open as before, the voltage is 12.2V. When I turn off the interior light that turns on with the hatch open, it goes up to 12.3V. There is still a red indicator light on the dash.

 

I guess I jinxed it by bragging on it a few posts back, but I got my moneys worth. I don't remember if it has a brand name and I haven't taken it out of the car yet but it is like this one. It says the brand name on this one is UPG.

 

you need a new battery jen, what is the warranty?

 

Thanks!

 

The Amazon listing says 1 year, and it's been a bit less than that, but it is up to 12.5 V today (65 deg F). It's hard to argue that it's failed completely if it's still functioning.

 

weather related failure is failure