Outer Limits 4x4 Board

What's everyones thoughts on using a Flooded Deep Cycle in a cranking application?

The slower charge rate may be an issue.

I imagine due to the lower plate surface area, internal resistance would be significantly higher, and recovery longer, yeilding a lower CCA.

BUT - would any of this actually effect the lifespan of the battery?
I'm thinking not.

Comments?

Paul

In term of a single battery setup, they are not designed as a start and charge battery, they are designed to have a current output for a fair while, and get a full charge again. that is when they last the longest. It would still last a fair while, but for the size it would not have the CCA as a regular battery of the same size.

You "may" buckle the plates with the high current drawn from batt.

Bazzle

deep cycle batteries have different plates to a normal car battery and you will cause damage to the plates if you discharge or charge them too quickly.

cranking off them would be a bad idea.

In regard to the plates - I have heard this theory - but never seen any evidence to back it up.

Thicker plates = stronger
Thicker plates = less surface area = lower CCA and slower recovery
Thicker plates = longer charge time
Thicker plates = less damaged by deep discharge - plates are structurally more suited.

Anyone know of any docs etc?

Thanx
Paul

me3@neuralfibre.com wrote:What's everyones thoughts on using a Flooded Deep Cycle in a cranking application?

The slower charge rate may be an issue.

I imagine due to the lower plate surface area, internal resistance would be significantly higher, and recovery longer, yeilding a lower CCA.

BUT - would any of this actually effect the lifespan of the battery?
I'm thinking not.

Comments?

Paul

i love deepcycle cranking!!

I've jump started my cranking battery off my deep cycle a couple of times just using jumper cables. Not sure if it does it any harm? Works when your stuck though.

Better to use a marine battery or AGM.

They are designed to do both (but aimed more towards cycling rather than cranking)

I've been using a deep cycle to crank for 4 years no probs

Not an expert, but my friend swears by his cat deep cycle, for the price he is going to set another up as an auxillary. By memory their just under $200

A deep cycle battery has a longer recovery time because it has more power stored, if you started the same car off a crank battery or a deep cycle battery they would be be recharged in the same amount of time.

Depending on the plate lay out will depend on the CCA raiting, some deep cycle have thick lead plates giving them a high A/H reading but a low CCA reading, the difference being the deep cycle will still be turning your engine over when the normal cranking battery died long ago IE it has more power and can keep putting that power out.

The only batteries where high discharge will irepaireably damage the battery are in AGM ( abosrbed glass matt), gel batteries or other batteries that aren't vented in any way, they will actually explode if heated to much.

I've found that the Supercharge MRV range of batteries to have incredible performace as both crank and deep cycle batteries, eg i have an MRV70 in my 4.2 diesel nissan patrol, it has 105 A/H deep cycle capacity but also 760 CCA, (the century n70 crank battery has only 600CCA by comparison even though it's the same size)

At the end of the day every one has their own opinion and what they've found works, my recomendation to you is not to get hold of ARB or TJM or any of them, get hold of a company that deals soley in batteries and find out what they recomend for you, or an auto electrician who also stocks batteries, not just fits them when needed.

If anyone has any questions regarding what i've just written please feel free to IM me, if i don't know the answer off hand i'll find out and get back to you.

i work at a battery retailer and an auto electrical workshop. we never advise cranking off a deep cycle battery.
its ok to jump start every now and then but theyre designed for two entirely different applications.
you have a cranking battery for starting as it has the ability to produce massive output for a short period of time and the opposite for deep cycle - small output over a longer period.
if using for winching, use a cranking battery as this will also draw too much from the deep cycle and cause damage.
if you want something inbetween then id suggest a yellow top optima. i think it has around 800cca and about 70ah from memory. your best bet is to look around for a dual purpose battery within your price range but id always recommend a second battery for accessories if you plan on running it down, unless space is a big factor.
is there a specific reason you want to use the deep cycle as a cranking battery? we should be able to work something out.

cheers,

Presto

p.s. www.howstuffworks.com is a great site for picking up things like batteries, ohms law etc and everything is explained very simply. helped alot with my apprenticeship

I agree totally with presto on the one, i actually worked for Battery World Sunshine Coast and now for Warana Auto Elctrical.

The Supercharge Allrounder i was talking about is a dual purpose like Presto mentioned, it's 760cca and 105ah and designed for both, from memory the MRV70 (which is the same dimentions as a patrol/cruiser battery) is worth about $265, compared to the Optima which are round $400 mark depending on the size you want.

battery world south canberra and lee and thomas auto electrics here mate haha. we dont deal with supercharge but yeah those optimas are bloody expensive. bloody good too tho, iv got one in my falcon thats 7 years old and been dead flat countless times but still going strong. i always use a c-tek charger tho so that could be half the reason its still in good shape

i used deep cycle on both landcruser & patrol for years no problem