Electronic/Battery Guru's question

[RandyO]

as a few here may know, I am slowly preping my V-strom, for an extreme arctic ride, as part of the prep, I have installed an auxiliary charging system that I am running independently from the bike's stock system. In making room for a second battery, I modified my exhaust from dual to 2 into 1, then chose an Optima DS46B24R yellow top, as my auxiliary battery

But, I'm finding it doesn't fit the way I would like, it's a little tall, and would require complicated recessing into my tail

SO, I am again looking at multiple smaller batteries, I would like to end up with more than 800 CCA. easily attainable with a couple gel snowmobile batteries, I am leary of lithium batteries in such cold. however would paring a gel battery with a lithium battery be advisable ?

[MUZ720]

The only issue I can think of is charging if needed? Although your bikes charging system should handle both! 12volts is 12 volts!

[RandyO]

The only issue I can think of is charging if needed? Although your bikes charging system should handle both! 12volts is 12 volts!

they will be independent of they bikes charging system, connected to the 75 amp auxialiary alternator

[SRTie4k]

From a brief Google search, a lot of results say not to wire lead acid and lithium batteries in parallel.

[MUZ720]

they will be independent of they bikes charging system, connected to the 75 amp auxialiary alternator

Nice clean system looks good.

[RandyO]

From a brief Google search, a lot of results say not to wire lead acid and lithium batteries in parallel.

but are not you doing that, when you jump start one with the other

I have read mixed, from it's an explosive hazard, to no problem, it solved my storage problem, but everything I have found so far, is with regard to solar storage, or RV, nothing automotive

My plan is for occasional engine starting and occasional use with engine off, with engine on, the system will power my auxillary lighiing, heated gear & electronic accessories. the only connection this will have with my bike, is a common ground, and one relay to light up the auxilliary system's volt meter & start switched circuits, when the bike starts

I will also have a "jump start" switch, so that I can jump start myself if necessary

[RandyO]

Nice clean system looks good.

One off prototype, a fellow V-stromer did the R&D when his stock charging system failed, when he sold the bike, he returned it to stock, and sold the setup to me, only machining I had to do, was extend the 3 stator bolt holes thru the side cover, to mount a bearing on the outside, and source 3 bolts from Mcmaster Carr, the rest was in the package I got from him. Crankshaft extension, bearing, pulleys, belt, belt guard, alternator, mount, and wire harness to battery. Besides machining several crakshaft extensions before settling on this one, he went thru several alternators, and pulley ratios, every alternator he tried, burnt itself out , till he found this one made for dragsters /high rpm What make sit look so clean, is the belt guard, trimmed from a belt guard on a Suzuki generator, kinda makes it look like it was a Suzuki option

[aldend123]

Wrap heated grip warmers around a couple lithiums? I don't know if that's inventive or ridiculous (both?), but it's an idea. I'd be really interested in making lithiums work, not just for the packaging size, but weight.

Lithium batteries warm up under load, so counter intuitively, drawing from them when weak from the cold heats them up and increases their effective CCA. But I guess I've never really considered if that's effective when it's below 0. Perhaps some insulating wrapping to keep the ambient air from cooling them?

[G21forme]

Yeah I gotta keep my litho Dewalt batteries on the dash to keep them warm. All of the solar work I've done tells me never mix batteries, lowest battery drops the entire system down. Probably rediculous but any chance you can mount a 15 watt solar panel to your saddle bags, that'll push a good 1ah at 14.6 volts with a controller and help with the cold.

[RandyO]

More than likely I will just use gel batteries in parallel, what I don't know, is how to calculate CCA with multiple batteries, do you just add em up, or is it a formula like resistors in parallel

my thinking, with a gel & lithium is that the gel would provide the initial amperage, while the lithium is "warming up" then the lithium would take over as the gel tapers off

[SRTie4k]

Everything I've read says that leaving lights on for 5 min is enough to warm a lithium battery enough to crank in below freezing temps. I actually just got a Antigravity lithium battery myself, and it struggles to crank my 1290 at 45F after sitting for a night in the garage, so I'm not entirely convinced yet.

What exactly is the use case for this build? Motocamping in winter?

[Stoneman]

What exactly is the use case for this build? Motocamping in winter?

I'm guessing his Kanc ride on February 7th? Or the occasional sprint to my house during snow storms to show off. Maybe even come torment me when I'm ice fishing?

[RandyO]

What exactly is the use case for this build? Motocamping in winter?

as I said in the initial post, "AN EXTREME ARCTIC RIDE" I dunno, -40°f, -65°f, it might only go to -20°, Deadhorse AK, in winter. I wanna be prepared, I will be running Rotella 0w40, it will be cold, and dark

however in summer, I will also have an inverter, and I might wanna plug in a toaster over

[Stoneman]

as I said in the initial post, "AN EXTREME ARCTIC RIDE" I dunno, -40°f, -65°f, it might only go to -20°, Deadhorse AK, in winter. I wanna be prepared, I will be running Rotella 0w40, it will be cold, and dark

As beet would say, "ta fuk wit dat"

As in, what the fuck is up with that?

[RandyO]

I'm guessing his Kanc ride on February 7th? Or the occasional sprint to my house during snow storms to show off. Maybe even come torment me when I'm ice fishing?

ya, that too

[Kurlon]

If you wire two matching batteries in series: Voltage doubles, Ah rating is the same as one of the batts.

If you wire two matching batteries in parallel: Voltage stays the same, Ah rating doubles.

[number9]

It was about 36 degrees today in Waltham and I saw a guy on a first-gen MultiStrada on my street. He had a decent jacket but was clearly wearing dress shoes and socks...

[RandyO]

If you wire two matching batteries in series: Voltage doubles, Ah rating is the same as one of the batts.

If you wire two matching batteries in parallel: Voltage stays the same, Ah rating doubles.

yes, but how does doubling the Ah, relate to CCA ? is what I wanna know

[Kurlon]

Amps is amps. If each batt can throw 400A for a min at 12v, and you pair them up, you've got 800A for a min at 12v now.

[Kurlon]

Now, that said, if the goal is an emergency jumper in the cold, relying on amps alone is likely not the solution. A small 6V or 12v batt in line with the starter will get the starter spinning faster than trying to out AMP it. That'd be my goto for cold weather, spin that thing up with some REVs.

[G21forme]

yes, but how does doubling the Ah, relate to CCA ? is what I wanna know

CCA batteries aren't / can't be rated in ah.

[boosten lebaron]

yes, but how does doubling the Ah, relate to CCA ? is what I wanna know

Ah and cca dont relate. Ah is the amount of storage and cca is the amount it can dump in say 30 seconds. Leisure batteries have massive ah but nearly zero cca. Car batteries have massive cca but very little ah. Then there are the dual one usually for boats that have a blend of the two.

I wouldnt go mixing different types of batteries if i could help it, especially for the cold that you want. Batteries get all crazy once the temps drop and having to worry about differing sets would be a hassle. I would want both sets to function 100% if the one set died. Even though you are seperating the systems you may find one dies so you need to use the other full time. At the very least they should be completely interchangable without much faffing about.

My concern for you is more the cold to start with. Can the batteries be insulated and heated somehow? Will the bike be stored outside at -20 and can you take the batteries inside with you? Do you have a way of warming the engine before hand?

Im thinking agm with insulation/heating is the way to go. Lithium isnt great in the cold as you know, you may find its cold for them to ever work properly.

[aldend123]

If you're starting a bike in a scenario where you expect CCA to be at it's minimum, like starting out on a -30F morning, isn't this getting too cold to start the bike at all? Won't you eventually either need a block heater or a fire under crankcase? Because if so, does that potentially nullify the importance of worrying about CCA?

[RandyO]

If you're starting a bike in a scenario where you expect CCA to be at it's minimum, like starting out on a -30F morning, isn't this getting too cold to start the bike at all? Won't you eventually either need a block heater or a fire under crankcase? Because if so, does that potentially nullify the importance of worrying about CCA?

that is why Shell makes Rotella 0w40, fwiw, I have gone on rides on my old SV650, down to -25, with 10w40, stored in cold, that was about the limits, if it didn't start right up, the first revolution, it wouldn't have made it to the next. When I an on road, I cannot count on the ability to plug in a block heater, and will likely add one, I'm liking Kurlon's idea, of adding a 6v in series, as a booster, max voltage of 18 should speed it up, without frying

[G21forme]

What about a hand warmer and a bit of mylar under the battery before you go to bed? No idea what you're up to Randy but super interested to hear about this adventure!