Lithium Race Batteries

Hi there

Searched the forum and found nothing. Have any owners ever invested and tried a lithium battery.

Barley red top do some, apparently they provide similar stats to their lead acid "15" race battery.

Messaging from my mobile so being lazy and not providing links, I'm considering one due to their excellent weight saving properties.
The lithium I was looking at weighed just over 1kg! Prices also aren't too bad either..

Thanks in advance,
Rush

I take it you're looking at lipo batteries. I have researched this quite a lot and I'm yet to find a way of recharging them safely via the alternator. Li-Po batteries will explode and burn violently when overcharged! You'd almost certainly need some sort of a controller/balancer and also you'd need to be able to use up waste current once the batteries are fully charged. I've been thinking about a hybrid system where you'd only use the lipo to start the vehicle (disconnect it afterwards) and then use a tiny motorcycle battery once the car has been started. Not sure it's worth the effort, I might do it just for the shits and giggles tho.

Ive used a lithium battery for the last couple of years.
Excellent weight saving, and pound for pound the best weight saving money can buy.

Very interesting Murray! What battery are you using exactly if you don't mind me asking? Did you just plumb it in instead of the original battery?

You are fine with Lithium Iron (not Ion) batteries, also known as LiFe or lithium iron phosphate batteries, the 2 wheel brigade use them a lot.

Li-Fe are safer, not entirely safe. See following manual for handling Li-Fe batteries, not sure how you're going to ensure proper charging in the car:
http://manuals.hobbico.com/hca/lifesource-manual-v2.pdf
Motorbikes are not the best example, they usually run these batteries in a total loss system, so they do not use alternator at all just recharge/swap batteries as necessary, and I bet the Barley batteries are designed to be run the same, as a total loss system in a race car. Not really suitable for anything else at the moment I'm afraid.

oifovo said:

Very interesting Murray! What battery are you using exactly if you don't mind me asking? Did you just plumb it in instead of the original battery?

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I am using a lithium ion battery that is supplied by a hillclimb competitor. Cant remember the exact name. Only weighs .9 kg
Wired it in just like the heavy battery that came out.

Murray said:

I am using a lithium ion battery that is supplied by a hillclimb competitor. Cant remember the exact name. Only weighs .9 kg
Wired it in just like the heavy battery that came out.

Click to expand...

I take it you're using it for racing then. Personally I would not use it even for that purpose tbh, especially not li-ion. I have been playing with lipo batteries for some time now and the risk of fire when overcharged is very high.

On a PC at the moment, the ones I were looking at are in the link below:

http://www.varleyredtop.com/products_lithium.htm

Particularly interested in the Varley Lithium Li-16 12V 16.1Ah Battery. Similar spec from what I can see to the PC680 I currently have fitted.

However I would be tempted by the Varley Lithium Li-5 12V 5.5Ah Battery, but not sure if the lower capacity would be an issue.


My car isnt a daily driver and doesnt run too many electrics (at most heater / lights / alarm / wipers(?)).

It's not about the electrics, when the car is running it takes its power from the alternator. The issue here is charging of lithium batteries - lithium batteries are a lot trickier to charge than lead acid batteries. Also, make sure you check what is the C rating of the battery you're looking at, the capacity is not the only parameter of importance! If the C rating is too low the battery will not be able to provide enough current to start the car. I know you said your car isn't a daily, but is it a dedicated race car used for maybe 20 minutes at a time? Or do you take it for a 2 hour weekend blast every now and again? The risk of overcharging will be even higher with a lower capacity battery...
If I ever get around playing with batteries (far to many things to do before that happens!) I will probably use two - a small lead acid motorcycle battery that will be kept in the car to support alarm and provide a "sink" for waste current from the alternator, and also a li-po battery that will be used for starting and will be switched from the cabing using a timer delay relay (which will cut it off after 30 seconds or so). This will be stored in a fire proof bag and recharged as required. As I said, it's more of a technical exercise and fun project rather than something that actually makes sense from practical point of view.

oifovo said:

I take it you're using it for racing then. Personally I would not use it even for that purpose tbh, especially not li-ion. I have been playing with lipo batteries for some time now and the risk of fire when overcharged is very high.

Click to expand...

I used it for racing and daily driven duties. No issues, and no issues with anybody that uses them.
Im not saying your wrong etc, im just saying ive had no issues.

Im not clued up with the science behind batteries, similarly to you, so much other rubbish to do before I make time to do this.

What is the C rating? Cranking current? Looking at the list of batteries I dont see this in the spec sheet.

When its driven it will be used for long drive most of the time, will see the track from time to time also. It isnt a stop and start daily type of car to do the shopping and pick the little one up in, if that is what you are asking.

Doesnt sound like it suits my requirements, but the weight saving makes it so tempting..

C rating is its current output, usually a multiple of its capacity. so a 5Ah Lipo may have a 50C rating which would be 50x5Ah = 250A discharge. you often have a continuous and burst C rating so the pack I have here is 30C continuous 50C burst(10sec). The C rating is usually defined by the geometry of the plates, big plates = high C.

Actually stop and start is probably better (safer) with these batteries, long drives are the worst as the battery takes a dip when you start the car and from there on it is just being charged. I have used plenty different types of batteries in my RC cars, so I know a thing or two about them but I'm not an engineer, so do take what I say with a pinch of salt. However based on what I know and my experience with these I would always advise to approach them with extreme caution, considering the relatively little gain and the possible consequences of them going wrong put me off risking using either a li-po or even li-fe in my car atm. Especially since there are alternatives which maybe not as light but are proven to work without major safety issues...

Unless your into competition I do not see the benefit versus the cost? Mine came with an Odyssey extreme racing 20, weighing in at a chubby 5.1kg..

Your battery is roughly £100
My battery was not a whole lot more and im saving over 4kg. Road or race car thats alot. Then consider a stock battery weighs 10-15kg?
Only downside was the battery didnt hold very long with an alarm armed. Max of two weeks.

Its a massive weight save over a standard car battery, I see they do a Li-3 (0.5kg) at £140 ish, if its up to the job I may get one myself, funds still required to get the car on the road first. Maybe I am tight but I still would not bother for a road car, with all the other stuff on the car would you notice? Maybe if it sits for long periods the Lithium holding the charge longer would be an advantage? What unit do you have Murray?