18 Ah AGM battery, Will it alone be able to.....?

[CR94]

I can tell you that Prius (factory) starting batteries fail like clockwork at 5 years.

What "starting batteries"? FYI, the 12-volt battery in a Prius does not provide the power that starts the engine. The large high-voltage "traction" battery does, and they typically last over 5 years.

I'm using a general-purpose 35 A·h AGM, which was a lot less expensive than 12-volt AGMs marketed for use in Prii. It seems to be nearing the end of its useful life now, at over 5½ years.

 

[Mark in NY]

Originally Posted by ragtoplvr
if you used the small odyssey then yes it would easily crank the engine we used to crank over a built 440 with one for racing. Note that race engines usually crank easier because of all the cam shaft overlap. Now though lithium is the hot ticket and even lighter.

Going off on a tangent here, but if there is a lithium starting battery out there that's reasonable in price (under say $400), will last a reasonable length of time in daily use (a couple of years anyway), and won't cause other issues in a modern vehicle, I'd sure like to hear about it.

Check out https://www.ohmmu.com/ for lithium batteries that are compatible with standard car alternator charging systems.

 

[LvR]

Check out https://www.ohmmu.com/ for lithium batteries that are compatible with standard car alternator charging systems.

Where do you get that info from on their website? ............................... To me, the use/application looks rather specific to only a few rather specific models

 

[wag123]

There are different kinds of batteries used in the higher quality jump starters than the UB12XXX gel cell batteries. I found this out when I replaced the battery in an excellent Booster PAC ES5000 jump starter box. The standard UB12180-UB12220 batteries are deep cycle batteries, the batteries used in the best jump starters are high discharge rate batteries which can easily output 450 amps or more, but they are also able to accept a very high charging current without damage after the vehicle starts. The UB12xxx gel cell batteries are not really suitable for this purpose because they don't meet either requirement. I tried using a UB12220 but it didn't get the job done. The battery that I ended up getting was the EnerSys Genesis G16EP 16AH AGM battery which has the same external dimensions as the UB12180-UB12220. Big difference in starting performance, but they are expensive. Alternatively, one could purchase a Booster PAC ES5000 jump starter and steel the battery out of it.

 

[Mark in NY]

Where do you get that info from on their website? ............................... To me, the use/application looks rather specific to only a few rather specific models

Yes, only a few sizes that you can possibly use on other vehicles based on the measurements of your OEM battery. They specifically targeted Tesla car replacement 12v batteries due to known early failure issues with original batteries (and maybe because Tesla owners are more prone to try new technology?) My recent positive experiences with replacement lithium batteries in place of OEM lead acid in other applications led me to look into lithium replacement for my car. My experience so far in those other applications has been very good indeed - more capacity with 60% less weight. The Ohmmu tech folks have been very responsive to my questions.

 

[wrcsixeight]

Since i can do so easily...i tried to start my 2 day cold engine on the 18 ah mightmax battery, by itself, again today.

It was able to turn it over slowly but it did not fire in the almost 2 seconds i let it crank.

I then tried the 1 year newer ub12220 the 22 ah battery and it fired up cranking only a bit faster

The wattmeters used are not.the same ones used on this original experiment 25 months ago.

But minimum voltage cranking on the unsuccessful attempt was 7.53.

The '600 watt' 18 ah mightymax battery holding 14+ v surface charge.

It's seen several dozen deep cycles in the 25 months since it originally was able to start the 2 week cold engine.

It has easiky jumpstarted about 6 strangers vehicles.

I always returned it to top charge quickly and topped it up no less than every 2.5 weeks when i had no work for it.

When charging at .constant 14.7v...amps stop tapering and start rising and heats starts increasing. That minimum amperage at constant votage is now 0.5 amps. A year ago it was 0.22.amps.

If let battery sit, and several hours later try again it will taper to less than 0.1 amp.

The ub12220 will taper to under 0.05 amps

If i wanted a higher CCA battery solely for jump starting, i'd now shop the mighty max offerings marketed for motorcycles which actually have a CCA figure.

Love Odyssey ... but 3x the price.

I dont like an AGM...absorbed glass matt, being called a gelcell.

There are actually gelled electrolyte sealed batteries in this size format.

Actual gelled electrolyte batteries can be excellent deep cycle batteries, but need more careful charging to prevent capacity killing voids from forming.