Anyone Using a Lithium Iron Phosphate Battery?

Shambler · Postby **Shambler** » Wed Jun 22, 2011 4:42 pm

In my case at least I find that the CarPC is actually draining power from the battery ever so slowly when the car is powered off. I should REALLY get around to putting in that isolation switch...

Scoota · Postby **Scoota** » Fri Jun 24, 2011 6:33 am

Hi Folks.

This has been a successful mod so far. The car has started every time I've tried with no hesitation. It's only been started about 20-odd times in the last month or so, but I'm very pleased thus far. I haven't finished fabricating the cradle yet, hence no photo. I'll be at Phillip Island next weekend, so I need to get it mounted this week! If you want to see how incredibly small it is ( the battery! :wink:

), please come and say hi. I drive a white NA6 with a dark grey hard-top, bronze wheels. It's my first sprint with the MX-5 club and my first time at The Island. So excited!

NitroDann, you are correct - the battery won't get drained when the car is running, but it will be under additional strain when I have the intercom, trip computer & interior/exterior lights all lit up during night rallies, potentially with the car turned off for extended periods. In that scenario I'd prefer to have a bit more capacity up my sleeve. And yes, the alternator will definitely be up-sized to supply the Hella's. A battery isolator will also go in soon.

For now though, I'm very happy with the battery. The long term performance and life-span remains to be seen, but I'm happy so far.

Cheers,
Trav.

rain902 · Postby **rain902** » Tue Sep 13, 2011 6:51 pm

i did some reading on these through hobbyworld.com - light, strong etc - while they may be a different chemistry (cant remember) there was something about them needing a stand alone charger - and saving additional weight of an alternator on board - anyone know anything about this?

japester · Postby **japester** » Thu Sep 22, 2011 1:49 am

What are you using to charge the Lithium battery?
All LiPo/LiFe/etc batteries should be balance charged, (where each cell is charged individually, not just run together in series), otherwise you will get cell voltage mis-matches and then, very soon thereafter, dead cells. They also hate being float charged.

(Spent a lot of time with R/C helicopters over the last few years, so have a few nuggets of knowledge floating around as I've observed the technology develop)

rain902 · Postby **rain902** » Thu Sep 22, 2011 1:57 am

japester wrote:What are you using to charge the Lithium battery?
All LiPo/LiFe/etc batteries should be balance charged, (where each cell is charged individually, not just run together in series), otherwise you will get cell voltage mis-matches and then, very soon thereafter, dead cells. They also hate being float charged.

(Spent a lot of time with R/C helicopters over the last few years, so have a few nuggets of knowledge floating around as I've observed the technology develop)

so how do we charge them in car? should they be charged outside the car then put in and if so, how much time do we get out of a battery that is trying to run an engine?

japester · Postby **japester** » Fri Sep 23, 2011 12:45 pm

rain902 wrote:
japester wrote:What are you using to charge the Lithium battery?

so how do we charge them in car? should they be charged outside the car then put in and if so, how much time do we get out of a battery that is trying to run an engine?[/color]

I'm thinking some kind of dual path feed. One from the alternator -> charging circuit -> battery, which then feeds the rest of the car.
Not sure how well that will work though, as the charging circuit should charge the cells, not run the car.

It will take a little bit of thinking 8-(

manga_blue · Postby **manga_blue** » Fri Sep 23, 2011 12:56 pm

The one I'd seen was an 8400mA R/C helicopter battery dropped in as a straight replacement for the original battery with the alternator still in place. It managed about 20-30 starts over the course of one track day with no problems. No idea about overall life expectancy under those conditions though.

Scoota · Postby **Scoota** » Fri Oct 21, 2011 1:09 pm

My battery wasn't supplied with a Battery Management System (BMS), but whilst researching similar products I did notice that many other suppliers do provide a BMS with their LiFe batteries. This suggests to me that it's probably a good idea, but I can offer nothing further on that. I'm not a battery guru. I wasn't prepared to fork out the extra dollars for a battery with a BMS. The supplier of my battery, LithBattOz don't recommend a BMS for this battery, so I didn't bother.

Time will tell if that was an ill-advised decision. As stated earlier in this discussion, I feel like I'm conducting an experiment on behalf of the good folks on this forum. So far it's been a good result, but the long term results remain to be seen.

kula · Postby **kula** » Sun Mar 18, 2012 10:29 pm

Im running one of these in my NA6.

http://www.braillebattery.com/index.php/batteries/b106

Never had an issue, starts fine.

Apu · Postby **Apu** » Tue May 13, 2014 9:56 am

With the battery in the Integra needing a 24hr re-charge over the weekend, I figured I might as well start looking at a lighter battery to replace it (and possibly the one in the MX5) in the near future.

I'm thinking a lightweight battery and would like to know if anyone is using one of these in their daily driver? Feedback please?

I also looked up the one kula posted - batteriesdirect.com.au have them listed at $229 which is an OK price. Not prepared to pay more that.

bruce · Postby **bruce** » Tue May 13, 2014 11:40 am

I do like the concept of a light, tiny battery. But the cost vs. life puts me off. My Suzuki battery (replacement Bosch) cost $120 and lasted nearly 8 years! These little batteries cost over $200 and the life sounds questionable.

Apu · Postby **Apu** » Tue May 13, 2014 11:47 am

Less of an issue on an MX5 as the battery is already in the boot, but in a front heavy car like the Integra, I'm also trying to shave weight off the front.

The Integra's replacement will be about $160 so bumping the $200 mark is kind of OK provided it starts the car fine for about 2 years before I need to pull it out for a full recharge.

I'd expect a Lithium battery to outlast a lead acid battery in the longer term, but again, asking for real life experience.

oztrackdays · Postby **oztrackdays** » Tue May 13, 2014 12:02 pm

I let mine go dead 100% flat, couldn't balance charge it due to being away from Home at Bathurst, it caught fire badly
was lucky to get away undamaged.

Back to an Odyssey for now.

Apu · Postby **Apu** » Tue May 13, 2014 12:17 pm

That would suggest jump-starting one of these buggers would not be a good idea...

cookie · Postby **cookie** » Sun May 25, 2014 4:22 pm

They're awesome batteries. In the boot it'll last 10 yrs or more. I had 10k worth of them to build a dirt bike but sold them and used Lipo. (1000A cont discharge, 3000CCA equivalent, 24aH 50v and only 4kg. But a mission to charge and physically fragile. These life batteries will handle a 4C charge rate (so 32a charge) and will be easier for the alternator to charge. (much much much lower IR.)