1. Attachments are working again! Check out this thread for more details and to report any other bugs.

Fitting mobility 12volt AGM battery.

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by Britprius, Mar 3, 2013.

  1. gamma742

    gamma742 Member

    Joined:
    Jan 9, 2015
    178
    73
    0
    Location:
    San Diego, CA
    Vehicle:
    Other Hybrid
    Model:
    Luxury
    @Britprius ... Are you still running on the Mobility AGM Battery? Should be what, about 7 years now?
     
  2. Britprius

    Britprius Senior Member

    Joined:
    Jun 14, 2010
    5,194
    1,912
    0
    Location:
    Herefordshire England
    Vehicle:
    2008 Prius
    I sold the car two years ago to a family member, and it is still running on the same mobility battery without any problems.
    I have replaced the Prius with a Lexus GS450H hybrid, and this also now has a 120 AH mobility battery fitted shortly after buying the car two years ago. The OEM battery is 80 AH so a 50% increase in capacity.
    The Lexus relies heavily on the 12 volt battery as videos can be run on all three screens while stationary as well as having heated seats front, and rear, and many other electrically operated features.

    John.
     
    R-P, SFO and Ramanjit81 like this.
  3. RBZ

    RBZ Junior Member

    Joined:
    Sep 1, 2014
    1
    2
    1
    Location:
    Hillsboro, Oregon
    Vehicle:
    2005 Prius
    Model:
    V
    After reading about this battery option in PriusChat a year ago, I purchased the smaller "electric wheelchair" battery for my 2005 Prius.
    UPG 85980/D5722 Sealed Lead Acid Batteries 12V; 35 AH; UB12350 ~$70 Walmart
    Yes, I needed to modify the Positive connection with a 12" 4Ga wire. I bolted the existing Negative cable through the Negative battery terminal. The UB12350 is smaller compared to the factory battery, so I secured the battery with wood wedges, tightened the connections down and it worked perfectly for the past year of everyday commuting and driving. 3 weeks ago I parked the Prius in my garage and left it unmoved. Maybe my door was not entirely closed, yesterday, would not start. I brought the little 12v battery back from the dead with a 3.5 amp NOCO genius running in 1 amp "repair" mode. It went from 10.2V to 12.3 now. I doubt that 20%+ resuscitation would be possible with the $200 OEM 12V. After I started the car, the traction battery was one pink bar. I drove 11 miles to the grocery store, recharged Traction battery, went shopping, started her up again and came home. I love all my 3 Prius. How is it pluralized?
     

    Attached Files:

    DT07Prius and milkman44 like this.
  4. milkman44

    milkman44 Active Member

    Joined:
    Oct 16, 2011
    591
    386
    0
    Location:
    Ky
    Vehicle:
    2010 Prius
    Model:
    II
    Those batteries are deep cycle batteries, so running it down shouldn't be a problem. I'm over three and a half years on mine.
     
  5. Petrodollar

    Petrodollar Member

    Joined:
    Feb 11, 2018
    53
    42
    0
    Location:
    USA
    Vehicle:
    2009 Prius
    Model:
    Four Touring
    A small sample platter of non-standard 12V batteries for the Prius. No endorsements are implied and the ordering does not imply any preference.

    Non-standard replacement for 12V AGM VR sealed lead acid (SLA) battery. Not drop-in. All need terminal adapters to convert from 6mm F11/F14/IT/C, 8mm F10/F12/F15, or NB/Flag posts to JIS Posts. Requires larger battery tray for S46B24R, Toyota P/N 74440-47020. All will fit, but may be tight, and battery compartment cover may sit up slightly.
    JIS Post - +/- about 15/13mm Dia. (SAE Post - +/- about 18/16mm Dia.)
    (Original S46B24R size - 237L x 128W x 200/222H mm (Body/Term.))
    Capacity in Ah at C/20 (20 hr) / C/10 (10 hr) discharge rates
    Cycles at 50% D.O.D. / 100% D.O.D., when capacity is reduced to 60% of new

    1. Duracell / East Penn Manufacturing PA, USA
    Ultra
    SLA, 229L x 138W x 203/208H mm, Term. - C (6mm Female) (Bolt M6)
    High Rate UPS, 10-Yr
    AGM VRLA DURHR12-225C/FR-A 55/?Ah ?/?cycles ?mohm T = -??C - +??C 38lbs (17Kg) Handle 3-Yr Warranty $160 +9 Core (Batteries Plus USA)
    Deep Cycle
    AGM DURDC12-55C/FR-F 55/?Ah ?/?cycles ?mohm T = -??C - +??C 38lbs (17Kg) Handle 2-Yr Warranty $165 +9 Core (Batteries Plus USA)
    (https://www.batteriesplus.com/image/pdfs/product-sheet/Duracell-Ultra-SLA-High-Rate-Product-Sheet-ID3701.pdf)
    (https://www.batteriesplus.com/image/pdfs/product-sheet/Duracell-Ultra-SLA-Deep-Cycle-Product-Sheet-ID1302.pdf)

    2. Power-Sonic Corp. CA, USA
    SLA, 230L x 138W x 207/214H mm, Term. - T6 (6mm Female) (Bolt M6)
    AGM VRLA 10-Yr High Rate PG-12V55 FR 60/56Ah ?/?cycles 8mohm T = -40C - +60C 36lbs (16.3Kg) Handle 1-Yr Warranty $160 +26 Shp (Battery Mart VA, USA) 144 +54 Shp (BatteryWeb FL, USA) 180 +20 Shp (Amazon AtBatt)
    230L x 138W x 220/230H mm, Term. - Universal Post with 6mm hole
    AGM VRLA Deep Cycle PDC-12600 60/55Ah 650/300cycles 8mohm T = -40C - +60C 39lbs (17.7Kg) Handle 1-Yr Warranty $149 +36 Shp (Battery Center GA, USA) 187 +55 Shp (BatteryWeb FL, USA)
    229L x 138W x 200/203H mm, Term. - T6 (6mm Female) (Bolt M6)
    AGM VRLA 10-Yr High Rate PHR-12200 58/55Ah ?/?cycles 5mohm T = -??C - +??C 38lbs (17Kg) Handle 1-Yr Warranty $131 +38 Shp (Amazon BatteryGuy Sales USA) 160 +0 Shp (Powerstride Battery CA, USA) 128 +32 Shp (Stored Energy Products USA) 143 +43 Shp (Allied Electronics)
    195L x 130W x 183H mm, + on right, 6mm Female
    LiFePO4 PSL-12450 45Ah @ C/5 2.5K cycles @ 100% BMS 13lbs (6Kg) $560 (BatteryPlex FL, USA) 600 (Battery Source GA, USA)
    (http://www.power-sonic.com/images/powersonic/sla_batteries/pg_series/PG-12V55_11_Jan_12.pdf)
    (http://www.power-sonic.com/images/powersonic/sla_batteries/PDC-12600_12_Oct_2.pdf)
    (http://www.power-sonic.com/images/powersonic/sla_batteries/PHRSeries/PHR12200.pdf)
    (http://www.power-sonic.com/images/powersonic/LithiumIron/PSL-12450.pdf)

    3. SigmasTek IL, USA
    SLA, 230L x 138W x 207/213H mm, Term. - IT (6mm Female) (Bolt M6)
    High Rate, 10-Yr
    AGM VRLA SPX12-200FR (12V56AH/IT) 56/?Ah ?/?cycles 5mohm T = -15C - +50C 40lbs (18Kg) Handle $132 +21 Shp (ReplacementBatteryStore.com NY, USA)
    General Purpose
    AGM VRLA SP12-55 IT (12V55AH/IT) 58/55Ah 450/250cycles 7.5mohm T = -20C - +50C 38lbs (17Kg) Handle $91 +? Shp (RBS)
    (http://sigmastek.com/files/specsheets/SPX12-200FR(IT).pdf)
    (http://sigmastek.com/files/specsheets/SP12-55(IT).pdf)

    4. Shenzhen Ritar Power Co. China
    VRLA, 229L x 138W x 211/216H mm, Term. - F11 (6mm Female) (Bolt M6) (Bolts included)
    Electric Vehicle EV12-55 55/52Ah 1250/750(80%)cycles 7mohm T = -20C - +60C 40lbs (18Kg) Handle $?
    Deep Cycle DC12-55 55/52Ah 675/350cycles 6mohm T = -20C - +60C 40lbs (18Kg) Handle $?
    Reserve Power AGM 12-Yr RA12-55A 58/55Ah 500/250cycles 6mohm T = -20C - +60C 39lbs (17.5Kg) Handle $?
    Reserve Power AGM 12-Yr RA12-55 58/55Ah 500/250cycles 6mohm T = -20C - +60C 40lbs (18Kg) Handle $105 +87 Shp (XpressBatteries FL, USA)
    (http://www.ritarpower.com/upimg/20171242712535.pdf)
    (http://www.ritarpower.com/upimg/20171241513131.pdf)
    (http://www.ritarpower.com/upimg/20179611457910.pdf)
    (http://www.ritarpower.com/upimg/20179611427555.pdf)

    5. Vision Group / Shenzhen Center Power Tech. Co. China
    VRLA, 239L x 132W x 205/210H mm, Term. - F11 (6mm Female) (Bolt M6)
    AGM 10-Yr 6FM55-X ?/55Ah 650/300cycles 7mohm T = -20C - +60C 38lbs (17.3Kg) $?
    AGM 10-Yr 6FM55S-X ?/55Ah 650/300cycles 7mohm T = -20C - +60C 38lbs (17.3Kg) $?
    AGM 10-Yr 6FM55E-X ?/55Ah 650/300cycles 7mohm T = -20C - +60C 34lbs (15.3Kg) $?
    LiFePO4 LFP12V-60AH 60Ah @ C/5 2.5K cycles @ 100% Protection Circ. 21lbs (9.5Kg) $?
    VRLA, 229L x 138W x 208/213H mm, Term. - F11 (6mm Female) (Bolt M6)
    AGM 10-Yr 6FM55T-X ?/55Ah 650/300cycles 7mohm T = -20C - +60C 40lbs (18Kg) Handle $?
    AGM 10-Yr High Rate UNA12-200 58/55Ah 450/250cycles 6mohm T = -20C - +60C 38lbs (17Kg) Handle $133 +25 Shp (1-Yr Warr, OSI Batteries MN, USA) 162 +0 Shp (1-Yr Warr, eBay 201986324449) 162 +0 Shp (1-Yr Warr, Amazon)
    (http://www.vision-batt.com/site/product_files/6FM55-X.pdf)
    (http://www.vision-batt.com/site/product_files/6FM55S-X.pdf)
    (http://www.vision-batt.com/site/product_files/6FM55E-X.pdf)
    (http://www.vision-batt.com/site/product_files/6FM55T-X.pdf)
    (http://www.vision-batt.com/site/product_files/UNA12-200.pdf)
    (
    Welcome to Vision Battery,VRLA battery,SLA Battery,AGM Battery,UPS Battery
    )
    (https://visionbatteryusa.com/series)

    6. Shuriken FL, USA
    SLA, 229L x 140W x 203/209H mm, Term. - 6mm Female (Bolt M6)
    AGM SK-BT60 60/?Ah ?/?cycles ?mohm T = -??C - +??C 38lbs (17Kg) Handle 1-Yr Replacement Warranty $176 +0 Shp (eBay 152704087433 the_wires_zone CA, USA) 170 +0 Shp (Amazon HiFi-Soundconnection MO, USA) 179 +0 Shp (Amazon The Wires Zone CA, USA)
    (1500W / 60AMP HOURS AGM 12V Starting Battery [SK-BT60] : Shuriken, High Performance Batteries)

    7. Winston Battery / Shenzhen Smart Lion Power Battery China (also Thunder Sky)
    LiFeYPO4, 5-10-Yr, 3K cycles @ 80%, 225L x 125W x 208H mm, Term. - 8mm Female (Bolt M8)
    "The monolithic 12V batteries do not have any PCM (any electronics) inside. They consist of finely balanced cells with identical perfomace."
    Does not have a protection board, charge control, or Battery Management System (BMS) built-in.
    WB-LP12V40AH 12.8V nominal (14.6V max) 40/?Ah 5mohm T = -45C - +85C 18lbs (8Kg) 1-Yr Warranty $249 +113 Shp (EV Assemble, China) 215 (GWL Power/EVPower, EU) 248 (EV Works, AU)
    (Shenzhen Smart Lion Power Battery Limited)

    8. Terminal Adapters (SAE models shown as example, must be modified to fit if used)
    F11/F14/IT/C/6mm Fem to JIS Post $?
    (?)
    For Britprius option 4: drill 0.25" (6.4mm) hole in center of JIS post, cut off clamp section, bolt JIS post to battery with 6mm bolt, assemble cable to battery posts as normal.
    Tin plated brass
    QuickCable SAE to JIS (Pencil Post) Conversion - Pos. 850350 $4 +3 Shp (BatteryMart.com)
    QuickCable SAE to JIS (Pencil Post) Conversion - Neg. 850250 $4 +3 Shp (BatteryMart.com)
    (Quick Cable: Conversion Adapters SAE to Pencil Post)
    (SAE to JIS (Pencil Post) Conversion - Positive: BatteryMart.com)
    (SAE to JIS (Pencil Post) Conversion - Negative: BatteryMart.com)

    Deka F11/F14/IT/C/6mm Fem to SAE Post 05457 Univ. 1-Pair $3 +3 Shp (BatteryMart.com)
    (http://www.dekabatteries.com/assets/base/TERMINALS_LUGS_FASTENERS_pages_21-32.pdf page 24)
    (Two Deka Power Sports Charging Posts with Ears: BatteryMart.com)

    Deka F11/F14/IT/C/6mm Fem to SAE Post 05518 Brass Polar 1-Pair $NA Discontinued
    QuickCable F11/F14/IT/C/6mm Fem to SAE Post 5512 Brass Polar 1-Pair $NA Discontinued
    XS Power F11/F14/IT/C/6mm Fem to SAE Post 580 Brass Polar 1-Pair $10 (eBay 282146153375) 14 (Amazon, Audiosavings) 12 (XS Power List)
    EnerSys Odyssey SAE Terminals F11/F14/IT/C/6mm Fem to SAE Post 3217-0006 Brass Polar 1-Pair $13 +3 Shp (BatteryMart.com) 16 (eBay 321608559098) 13.50 (Amazon, BatteryMart)
    (https://4xspower.com/shop/accessories/terminals/580-top-terminals)
    (http://www.odysseybattery.com/documents/US-ODY-ACC-AA.pdf)
    (Odyssey Battery Terminals | SAE Battery Terminals | Battery Mart)

    EnerSys Odyssey SAE Terminals 3/8" Male to SAE Post 3217-0049 Brass Polar 1-Pair $8 (eBay 222872146937) 13 (Amazon, BatteryMart) 3.56 +8 Shp (Summit Racing)
    XS Power F11/F14/IT/C/6mm Fem to 3/8" Male 590 Brass 1-Pair $15 (eBay 272814778261) 18 (XS Power List)
    XS Power F11/F14/IT/C/6mm Fem to 3/8" Male 587 Zinc Steel 1-Pair $12 (eBay 302621759857) 12 (Amazon, Audiosavings) 12 (XS Power List)
    (http://www.odysseybattery.com/documents/US-ODY-ACC-AA.pdf)
    (https://4xspower.com/shop/accessories/terminals/590-adapter-studs)
    (https://4xspower.com/shop/accessories/terminals/587-studs)

    VMAX F10/F12/F15/8mm Fem to SAE Posts VCP8 Stainless Steel Polar 1-Pair $15 (VMAXTanks.com) 14 (eBay 302264319661) 12 (Amazon, bargainshore)
    (VCP8 8mm Stainless Steel Charging posts )

    QuickCable NB/Flag to Top Post (16mm SAE -) BPAdaptor 850116 Univ. 1-Pair $7.00 +7.50 Shp (BatteryStuff.com)
    Deka NB/Flag to SAE Post 02033 Univ. 1-Pair $3 +3 Shp (BatteryMart.com)
    (Quick Cable: Conversion Adapters Specialty Terminal with Pole to Top Post)
    (http://www.quickcable.com/doclib/d0662.pdf)
    (EZ Red | Automotive Battery Post Adapter)
    (http://www.dekabatteries.com/assets/base/TERMINALS_LUGS_FASTENERS_pages_21-32.pdf page 25)
    (Flag to Post Terminal Adapters: BatteryMart.com)

    9. Terminal Hardware (Screws, Flat Washers, and Spacers to simulate JIS posts)
    Hillman Hex Cap Screws Metric Stainless Steel M6-1.00 x 25mm 882080 dwr A33 5pcs $1.93 (Lowe's 136491)
    Hillman WeatherMax Stainless Steel Flat Washers #12 (14mm OD) 126877 24pcs $1.98 (Lowe's 409087)
    Hillman Flat Washers Metric Stainless Steel 6mm (12mm OD) 882098 dwr A33 5pcs $1.92 (Lowe's 44342)
    Hillman Flat Washers Stainless Steel 1/4" (16mm OD) 830502 bin ZAA 1pc $0.22 (Lowe's 311726)
    Chrome Steel Spacers 1/4" ID x 3/4" L x 1/2" OD (6.4 x 19 x 13mm) 13682 1pc $2.65 +5 Shp (Bolt Depot MA, USA)
    Chrome Steel Spacers 5/16" ID x 3/4" L x 9/16" OD (8 x 19 x 14mm) 13694 1pc $2.74 +5 Shp (Bolt Depot MA, USA)
    (
    Spacers, Chrome plated steel, 1/4" x 3/4" (1/2" O.D.) - Bolt Depot
    )
    (
    Spacers, Chrome plated steel, 5/16" x 3/4" (9/16" O.D.) - Bolt Depot
    )
    (
    Spacers, Chrome plated steel - Bolt Depot
    )
    Everbilt Chrome Steel Spacers 5/16" ID x 3/4" L x 5/8" OD (8 x 19 x 16mm) 369-401 2pcs $3.87 (Home Depot 800304)
    Stainless Steel Spacers 1/4" ID x 3/4" L x 1/2" OD (6.4 x 19 x 13mm) 2pc $10.95 (eBay 222593142246)
    Stainless Steel Spacers 1/4" ID x 3/4" L x 5/8" OD (6.4 x 19 x 16mm) 2pc $11.20 (eBay 322531091383)
     
    #365 Petrodollar, May 2, 2018
    Last edited: May 2, 2018
  6. DT07Prius

    DT07Prius Junior Member

    Joined:
    Jul 23, 2018
    1
    0
    0
    Location:
    Los Angeles, CA
    Vehicle:
    2007 Prius
    Model:
    Touring
    I just purchased

    I'm hoping this battery will work. Does anyone have photo's of how you adapted the vent tube to work with these batteries?
     
  7. PriusCamper

    PriusCamper Senior Member

    Joined:
    Mar 3, 2012
    10,917
    4,426
    0
    Location:
    Pacific Northwest, USA
    Vehicle:
    2007 Prius
    Model:
    Two
    As far as I know there's no vent tube in the wheelchair battery. So just remove the vent tube... There hasn't bee a tube on the two wheelchair batteries I've installed... So if anyone needs a Prius 12v vent tube? Lol...

    As for that OEM battery ever making use of that vent tube in the first place, I suspect it'd only happen if there was a car accident type damage or massive amount of overcharging, both of which are going to be way bigger challenges than if you have a vent tube or not.

    The main hassle in using wheel chair batteries in my experience via the most popular $130 Batteries Plus batter in US is adapting the terminals bolts with 1/2" and 5/8" bushings and more bolt length so you don't have to change the battery cable terminal that the car normally connects with. Most hardware stores have something that works, but I hope to find something that's a little more bomb proof and doesn't depending solely on bolt tightening to stay in place.
     
    DT07Prius and SFO like this.
  8. milkman44

    milkman44 Active Member

    Joined:
    Oct 16, 2011
    591
    386
    0
    Location:
    Ky
    Vehicle:
    2010 Prius
    Model:
    II
    Couple of days ago, the wife went out to go to the Dr., came back in the house and said the car wouldn't start. I went out and even the dome light wouldn't come on. The 35 amp mobility battery is just over 4 years old and I thought it was a goner. As soon as I hooked up the jumper, the dome light came on. I put the charger on and left it for about 12 hrs and all is well again. Did I mention that it is a deep cycle battery?

    UPG UNIVERSAL BATTERY UB12350,NEW | eBay
     
    Raytheeagle and PriusCamper like this.
  9. bisco

    bisco cookie crumbler

    Joined:
    May 11, 2005
    107,762
    48,974
    0
    Location:
    boston
    Vehicle:
    2012 Prius Plug-in
    Model:
    Plug-in Base
    you will still need to keep an eye on it for awhile
     
    Mendel Leisk likes this.
  10. exstudent

    exstudent Senior Member

    Joined:
    Jul 11, 2009
    2,212
    900
    0
    Location:
    Torrance, CA
    Vehicle:
    2007 Prius
  11. eximage

    eximage Junior Member

    Joined:
    Aug 27, 2006
    13
    2
    0
    Location:
    Union City CA
    Vehicle:
    2001 Prius
    Model:
    N/A
    I'm ready to purchase the smaller size Ritar RA12-33 for my 2005. Is adequate for models with SKS?
     
  12. milkman44

    milkman44 Active Member

    Joined:
    Oct 16, 2011
    591
    386
    0
    Location:
    Ky
    Vehicle:
    2010 Prius
    Model:
    II
    The 12350 listed above has worked well with my '10 with SKS for over 4 years and the price is for new battery, the link I posted was just for reference. They are available on Amazon for the same price and free shipping with Prime.
     
    Raytheeagle likes this.
  13. dolj

    dolj Senior Member

    Joined:
    May 14, 2012
    7,504
    3,772
    0
    Location:
    Wellington, New Zealand
    Vehicle:
    2007 Prius
    Model:
    N/A
    While I can't comment on how well a Gen 3 (such as milkman44's above) uses and looks after the 12 V when compared to a Gen 2 like yours, as a Gen 2 owner, my advice would be to not go with a battery rated with a lower capacity (this Ritar is 33Ah@10hr-rate) than the stock non-SKS battery (35 aH). The minimum for SKS should be 45 Ah@10hr-rate.

    I have a 55Ah@10hr-rated AGM deep cycle battery in my non-SKS Gen 2 and I still have to charge it externally every 2 weeks, even though it gets, at least, 2x 20 min drives 5 days a week. I'm sure that without doing this external charging my battery would last well over 5 years. I just want it to last much longer than this. I also have a SKS Gen 2 with a regular non AGM 12 V (same physical size as SKS stock battery) and it does even worse.

    YMMV.
     
  14. R-P

    R-P Active Member

    Joined:
    Dec 6, 2011
    804
    288
    0
    Location:
    Netherlands
    Vehicle:
    2009 Prius
    Model:
    II
    I agree. While good AGM's will deal better with lower discharging, not discharging them so much will always be the better option. And discharging 10Ah* from a 33Ah will leave you 23Ah or ~70%. Discharging 10Ah from a 55Ah will leave you 45Ah, or ~80%. Given same (lead) chemistry, a periodically 20% discharged battery will always outlive a periodically 30% discharged battery.

    What's your reason for doing this? We have the same (Gen 2-non-SKS, 5days*2x20km/week, 55Ah AGM) and I didn't see a reaon for this yet. Besides those kilometers we also have some erratic 100-1000km a month besides the above mentioned km, but still curious...

    (The only time I DID charge it externally was after I dropped by your house on the exact opposite side of the earth (y) and the Prius stood still for 9 weeks...Upon our return home, I started it, drove it 10 meters closer to a powersocket and charged the 55Ah battery (unfortunately without testing the battery voltage))

    * don't have a clue, but 10Ah might be 20 days of SKS + rest of the static drain of the Prius? Just ballpark figure.
     
    #374 R-P, Nov 15, 2018
    Last edited: Nov 15, 2018
  15. eximage

    eximage Junior Member

    Joined:
    Aug 27, 2006
    13
    2
    0
    Location:
    Union City CA
    Vehicle:
    2001 Prius
    Model:
    N/A
    I've read that Harborfreight has this battery that they sell for their solar array. I have a gift card that i can use. They have 2 seeming identical batteries SLA or Universal. they both are AGM. The SLA shipping weight is 4# heavier. Any opinions. thanks
     
  16. PriusCamper

    PriusCamper Senior Member

    Joined:
    Mar 3, 2012
    10,917
    4,426
    0
    Location:
    Pacific Northwest, USA
    Vehicle:
    2007 Prius
    Model:
    Two
    Well... I think I was on this thread 5 years ago when I bought the best selling 12v 55ah mobility/backup home computers power supply battery for about $120. In the past 6 months or so my car has had a problem with the headlights not turning off when door opens and I've had more than once received a late night text from the neighbor alerting me. Every time the 5 year old battery has not missed a beat from accidental drain.

    If you were to buy a harbor freight battery and after 5 years you had the same problem as me your car wouldn't be going anywhere the next day. And after a few times of this, you'd be shopping for a new battery rather than simply being grateful you put the very best biggest 12v that will fit in the space.
     
  17. R-P

    R-P Active Member

    Joined:
    Dec 6, 2011
    804
    288
    0
    Location:
    Netherlands
    Vehicle:
    2009 Prius
    Model:
    II
    And in general, so not knowing the specific battery/brand/seller, and with the knowledge I think I have:
    Get the heavier battery. High cranking amps come from a large surface area of lead: loads of lead at the surface with the battery acid (in the Glass Mat incase of an AGM) to have the chemical reaction take place and thus be able to produce a huge current.
    The Prius 12V battery does not have to produce a starting current, so it doesn't need such thin leadplates. In that case, the leadplates can be thicker (is heavier in the same footprint of a battery), and guess what, thicker leadplates warp less easily: one of the causes starting batteries die is warped leadplates shorting out against the opposite polarity lead plate next to it.

    But that's just me hearing the bell ring without knowing where the clapper is (funnily enough we have the exact same saying in Dutch).
     
  18. PriusCamper

    PriusCamper Senior Member

    Joined:
    Mar 3, 2012
    10,917
    4,426
    0
    Location:
    Pacific Northwest, USA
    Vehicle:
    2007 Prius
    Model:
    Two
    Agree with all that you said as to how Prius 12v is a different use than a car with just a gas engine... Which also means the best battery is not one with the highest cranking amps, but the one with the most amp-hours, which means as the battery get older and you have an issue with headlights left on, or cars sits for a long time, the longer lasting amp-hours will allow your battery to still have a charge so the car can still boot back up into ready mode. As per my previous post...
     
    Simtronic likes this.
  19. R-P

    R-P Active Member

    Joined:
    Dec 6, 2011
    804
    288
    0
    Location:
    Netherlands
    Vehicle:
    2009 Prius
    Model:
    II
    I should have quoted Eximage, as I was more or less answering his question, only incorporating your reservations regarding Harborfreight. So in no way meant as a (condescending) comment on what you said ;)
     
    PriusCamper likes this.
  20. dolj

    dolj Senior Member

    Joined:
    May 14, 2012
    7,504
    3,772
    0
    Location:
    Wellington, New Zealand
    Vehicle:
    2007 Prius
    Model:
    N/A
    I'm a bit late returning to this thread, so, my apologies for the late reply.

    I notice that if I don't (externally) charge at all the battery seems to be in the low 12.x range. As Pb/Acid batteries don't like to be in any state of discharge, I like to keep mine fully charged as much as possible. Primarily, it is a personal experiment to see just how long this battery will last being looked after in this way.

    @R-P, it is a shame you didn't measure your battery voltage before charging it up. It would have been interesting to know what the voltage was after sitting for so long.
     
    #380 dolj, Nov 22, 2018
    Last edited: Nov 23, 2018