Fitting mobility 12volt AGM battery.

I don't see anywhere to connect the vent tube. It says not to charge in an enclosed space, and that is just what your Prius cabin is.

 

What posts did you use with that?

 

Posts? Not sure what you mean? This thread was started years ago... I found this particular battery last Winter and since then my friends and I have bought several of them and are very pleased with both the performance and the ridiculously low price with no core deposit, which means $10 store credit at advance auto parts for bringing the old battery in!

 

Please read through this whole thread! The vent tube is uneeded BS... The mobility batteries are certified to work in all enclosed spaces even hospitals right under the butt of the person using the mobility device. If there was a need for venting for safety for these batteries they would have them. Wheelchair batteries have higher safety requirements than a car battery will ever have. The auto industry is slow to adapt to battery quality improvements and from a liability perspective, they think it's better to not eliminate no longer needed safety features.

 

In the link you posted, the pictures show a battery without posts, the things you clamp the cables onto. Are they included and just not pictured or ..???

 

You have to adapt them...

I've tried several different methods as I've learned more over the years. The one I like best these days is the least expensive and simply means going to the hardware store and buying slightly longer bolts than the ones it comes with and then adding big thick metal washers on both sides of the terminal and bolt it down that way...

I've also used a stack of washers on the bolt to simulate a post, which is more problematic. @Britprius the first time had me cutting off the old lead posts of previous battery and drilling a hole through them and bolting them in place. I didn't like that way at all, mostly because I don't have a drill press.

And more recently a person on here spent a fortune on the exact terminal using this graphic:

 

Newer members here would do well to read the other threads about this too, before deciding just which is the BS. There is more to this battery venting issue than just battery quality. Automotive electrical safety standards are not up to the same levels as medical device standards, so appealing to the latter is not sufficient to hand-wave this issue away.

 

The point is there are absolutely zero incidences of any death or injury from lack of venting with the exception of a lone incident on a turnpike where a mom & kids died from noxious fumes and while they couldn't prove that it was directly cause by the 12v, it was the only option they couldn't exclude.

If there was any concern about the safety of un-vented batteries there would multiple incidences that could be directly traced back to and proven to be the battery and none of that evidence has ever existed.

 

I had a battery under the hood explode when I turned the ignition key. I would say under the hood is well ventilated. If there is a vent on the battery it needs to be vented out of the cabin. Otherwise it better be a sealed battery, no vent!

YMMV

 

You contradicted yourself in the same sentence.

They did prove that the victims had elevated levels of hydrogen sulfide in toxicology tests, that the 12V battery in the vehicle passenger cabin was not its original battery, and that is was the wrong type for the vehicle. There were also other indicators.

That BS comes from viewing this through very narrow blinders.

Take off those blinders to look a bit wider, and one will find plenty of hydrogen sulfide fatalities in and around workplaces from various causes, including severe battery charging mishaps. One will also find additional laboratory proof of hydrogen sulfide emissions in certain catastrophic battery charging failure circumstances.

Your lack of finding similar cases in medical environments is testimony to the much more stringent electrical and other safety standards in medical equipment. Automotive equipment has much less stringent regulation, and the vast majority of passenger vehicles don't have 12V PbS batteries inside their passenger compartments.

Other reading wishing more background before choosing to skip venting, can start here:
12 volt hack for Gen 1- Gen 3 | Page 2 | PriusChat

 

Additionally there is zero evidence of a Prius ever offering anything more than ~14v charge to the 12v battery, which covers all of the primary risk of "catastrophic battery charging failure circumstances."

What's more whats been reiterate on this thread again and again is that mobility batteries for wheel chairs are at much greater risk of overcharging sources and humans using them are much, much closer to them, yet no pressure relief valve/venting system that you're irrationally loyal to exists because the battery by every measure of the manufacturer is perfectly safe enclosed inside a ventless case.

Go back and read the article... The battery itself didn't show evidence of discharge and maybe they can't entirely exclude it as a source, but do you have any idea how common Safety and Health Topics | Hydrogen Sulfide - Hydrogen Sulfide in Workplaces | Occupational Safety and Health Administration really is?

And we're talking about a single incident on record. How many deaths did Firestone tTre find was acceptable annually due to product defects before they got in trouble? As in you need lots of evidence of people dying from ventless batteries to prove your point.

Your online misplaced fear advocacy is not healthy for you or anyone else...

 

I am kinda disappointed that nobody commented on my longish post Fitting mobility 12volt AGM battery. | Page 23 | PriusChat

As @Britprius is absent in this thread since a while I would like to get your opinion.
I read through the whole thread (I took me a week) but I regret that I didn't make more notes.

SLA - Sealed Lead Acid
VRLA - Valve Regulated Lead Acid
AGM - Absorbent Glass Mat

Originally used Ritar RA12-55 is a battery suitable for: UPS/EPS, Telecom, power grid, medical equipment, emergency light and security system applications. It has 12 years of design life in float service.

I have chosen Power-Sonic PG-12V60 PG-12V60 12V 60Ah Long Service Life VRLA Battery | Power Sonic
as it is available for £100 and also designed to offer high-rate discharge for UPS, telecoms, emergency light and security systems. It is also similar weight and life expectancy up to 12 years in standby mode as Ritar.

Do I really need a deep cycle battery knowing that Prius is drawing only around 20A for the first 10 seconds or so?

Thanks.

 

There are two (possibly more) gases that can be emitted from lead-acid batteries: (1) Hydrogen Sulphide (poisonous) may be emitted when a lead-acid battery is overcharged; (2) Hydrogen (not poisonous but forms an explosive mixture in combination with air in certain proportions) may be emitted under normal charging conditions -- and the concentration could reach that dangerous level in the confined space of the Prius battery compartment.

Mention has been made of the use of un-vented batteries in medical equipment, but the charging circuitry of medical equipment is undoubtedly designed to a higher standard than that used in cars -- especially cars in which a vented battery (with the vented gases/vapors being led outside the car's enclosed space) is specified.

The charging circuitry for deep-cycle batteries is different from that used for AGM batteries. E.g., I have a standby power supply consisting of two GC2 golf-cart batteries in series, and the manufacturer recommends a float voltage of 13.2 Volts -- not the 14 Volts that you say the Prius charging circuit supplies. Maybe a deep-cycle battery used in a Prius would be in a permanent overcharge state.

 

Charging
To obtain maximum service life and capacity, along with acceptable recharge time and economy, constant voltage-current limited charging is recommended. To charge a Power-Sonic SLA battery, a DC voltage between 2.30 volts per cell (13.8 V float) and 2.45 volts per cell (14.7 V fast) is applied to the terminals of the battery.

Caution: Never charge or discharge a battery in an airtight enclosure. Batteries generate a mixture of gases internally. Given the right set of circumstances, such as extreme overcharging or shorting of the battery, these gases might vent into the enclosure and create the potential for an explosion when ignited by a spark. Generally, ventilation inherent in most enclosures is sufficient to avoid problems.

https://www.power-sonic.com/wp-content/uploads/2018/12/Technical-Manual.pdf

 

You don't have to adopt anything if you use the internal threaded battery I posted. I added nothing in hardware. Had some leftover parts.
It's all here in the beginning of the thread....

 

This thread started in March of 2013... I don't see any post from you then. Are you referring to a different thread? Can you please post a link to the thread you are referencing? Thanks!

 

interesting thoughts, but a couple issues:
First of all, my deep cycle battery IS an AGM battery. So obviously no difference in charging circuitry.
Secondly, are you aware that the entire battery compartment on a Prius is vented to outside? The exhaust from the hybrid fan whistles right through the battery compartment to the flap venting it outside.
I happened to prop my flap open with a clip to assist the ventilation process.
But that compartment certainly isn't sealed.
Me thinks folks are freaking out about worst case scenario and it just isn't going to happen. The super paranoid could wire a 12 volt fan that would be installed in that air vent, ensuring constant exhaust from the battery compartment, that would be cheap and easy.

 

I am absolutely referring to this thread in particular, the information is all here, with pictures. No I didn't post it years ago, I read it. The entire thread..
and that's what you have to do too, read the entire thread, if you want to understand it fully. at least read the first couple of pages, that's where all this stuff is...
Thanks in advance!

 

Thank you for being rationale and intelligent about this... Back in 2013 when this thread started BritPrius use to talk in private messages about all the folks who have nothing positive or supportive to say about this idea and how they're constantly failing to prove their point. In this regard your comments are very much appreciated.

 

In the lower right corner of every post in a thread is the post number. Can you please let me know which post number you are referring to? This thread has almost 500 posts and I / we don't have time for that level of reading on a Monday.