I prefer lipo only because it's cheaper

Everytime I see this thread topic I laugh. It is like having a thread titled "I only like having Sasha Grey as my girlfriend because she makes a really great cup of coffee". The cheapness (or otherwise) of lipo is probably the very last consideration I factor in when choosing it as my preferred chemistry.

Don't get me wrong, I like cheap (and I like good coffee), but there is a few things I am really enjoying before I get to that.
 
I think you're all forgetting about headways. you can get them at 1.3usd per Ah from the factory. So for a 12S1P of 38120's you get 39,6 10Ah nominal and able to 10C discharges and 5c charges rates witch is good for most people.

Just to compare:

12S1P of 38120's : 39,6v 10Ah - 396Wh - 3.96Kg - 156USD (just the cells) - about 2.53Wh/$ - 1000~1500 cycles

10S2P of Turnigy LiPo: 37v 10Ah - 370Wh - 2.66Kg - 142USD (just the packs) - about 2.60Wh/$ - 400~500 cycles

so lipo is about 37% lighter and a bit cheaper, but you still have the plug'n'play of the LiFe(with a good bms of course), the safety and twice or more lifecycle at almost the same price.
 
I like both, lifepo4 for one type of use and lipo for another.

Right tool for the job is the logical choice. Decisions based entirely on cost are stupid. Cost per cycle is a factor, but not the most important thing to be considered.

When I want to rip a 16" 2x6 into 1x2's, do I choose a sawsall? No, I use the right tool, a table saw. Same logic should be how you choose your battery, your controller, your bike, your motor, etc.
 
Last year when I was looking to replace my tired 8 amp hour nicad.I was considering between a ping and the lipo's from hobby king. I already had a 48 volt pack and I wanted to go up in voltage to 72 to increase my performance and reduce the weight I was carrying. I ended up going with the lipo because it was a less expensive up front cost among other things. I got an Icharger, some silicone wire, a bunch of connectors and 3 zippy 8 amp hour 6s batteries plus shipping to Canada for a little under $500. At the time I was only running a little 20 amp controller but event that would have required that I got at least a 15 amp hour ping. So comparing the 60v 15 amp hour ping that's almost $700 before shipping. It's quite a bit more expensive up front. The pings would also be quite a bit heavier too and the low c rate sucks. Now that I'm using a 40 amp controller the pings are completely out of the question and I plan on moving up to 60 to 65 amps soon.

I've been running my lipo's just about every single day for almost a year now. Half the year I've been discharging down to about 22.8 and charging twice per day. My batteries are still performing well enough. I'm pretty happy with my lipos and plan on getting more soon. I would like to give the a123's a go but they are pricey up front. One thing I don't like about the lipo's is the charging. I charge one pack at a time and I balance charge every single cycle because I don't want to have a fire. One big benefit to the lipo is the modularity. I really like how easy it is to add or remove packs to increase voltage or amp hours.

Anyone running a123's and have gotten close to 1000 cycles or more? I figure I'm probably somewhere around 300 to 350 cycles on my lipos and still going good.
 
electron you can bulk charge your lipo rather than charging them once at a time.

With the charger from BMSBattery you can ask them to set to the right voltage. These charger can't do balance charge, but you probably don't need to balance your pack for every charge.
 
Yeah I've seen others on here bulk charging but it occurs to me that every lipo fire I've seen happened during bulk charging. I guess I can experiment a little with the fast charge or regular charge modes on my Icharger and see how that goes first. My pack is quite small only 8 amp hours, 66.6v but I will need to get a better charging setup when I increase my pack size.

One problem for me is I always charge in the house and I'd be pretty paranoid about bulk charging there, does anyone even do that?
 
If you are paranoid about the lipo fire, you can either:
- Only charge to 80% for safe margin
- Or buy 2 hyperion charger1420i to balance charge at once your 66V lipo.
 
I never bulk charge, the rc community abandoned that method years ago due to all the fires.
 
Pure said:
Perhaps not that fast but it does seem to constantly be evolving/getting better. I know the LiPo of 2 years ago was twice the price and dangerous as hell, with crap discharge rates.

I have a 2.5yo turnigy 20c lipo pack. It is no worse than the ones I bought recently. The nanotechs seem to be better yet I can't see how they're that much safer.

kfong said:
I never bulk charge, the rc community abandoned that method years ago due to all the fires.

RC guys don't bulk charge because the industry had to find way defend the batts against reckless users who treated them like toys. So they sell intelligent RC chargers that won't charge 0V lipos, nor will overcharge any. If you are as intelligent as the charger, why worry. Moreover, the charger can't see the lipo is puffed. You can. That said, if someone ever makes a quality 20s charger that costs under $250, I'm all over it.
 
Just get two Hyperions 1420 and network them together. This will give you 24S. The balance taps on rc chargers can detect bad packs easier than you can. Weak cells won't always puff up until it's too late. Balancing your packs will keep them healthy. Hyperions have lots of other features, just go to the Hyperion thread. Bulk charging with such large packs, it's very easy for one cell out of 20 to go out of balance and create a dangerous situation. The larger the packs the more diligent you need to be. I would be implementing any and all saftey methods as possible. We have been seeing a lot of ebike fires over the years and I expect to see a lot more with the increase in user base. Just look at the large number of RC fires should convince you that they will happen. I balance charge every time with my Hyperions, It's very easy with the way I've set it up using a db25 connector for the balance taps. I've posted it on some of my threads. I feel comfortable charging it while in the house doing other things. The charger will fault out if something goes wrong where as a bulk charger will keep on charging, oblivious to any problems.
 
kfong said:
Just get two Hyperions 1420 and network them together. This will give you 24S. The balance taps on rc chargers can detect bad packs easier than you can. Weak cells won't always puff up until it's too late. Balancing your packs will keep them healthy. Hyperions have lots of other features, just go to the Hyperion thread. Bulk charging with such large packs, it's very easy for one cell out of 20 to go out of balance and create a dangerous situation. The larger the packs the more diligent you need to be. I would be implementing any and all saftey methods as possible. We have been seeing a lot of ebike fires over the years and I expect to see a lot more with the increase in user base. Just look at the large number of RC fires should convince you that they will happen. I balance charge every time with my Hyperions, It's very easy with the way I've set it up using a db25 connector for the balance taps. I've posted it on some of my threads. I feel comfortable charging it while in the house doing other things. The charger will fault out if something goes wrong where as a bulk charger will keep on charging, oblivious to any problems.

You can also bulk charge with a set of lipo alarm. That's way cheaper than purchasing 2 hyperion charger + 2 power supply = $300
 
It's a small price to pay vs. what can be damaged by a fire. An alarm won't be heard while in the house. Its best to do things right and not find out afterwards that you cut corners only to loose a house due to bad judgment. Everyone has there own take on what is safe. For me this is the path I choose to go with.
 
It seems like Lifepo4 is best in terms of range, number of recharge cycles etc. but they are fairly expensive. I'm also confused on what you are trying for. Would you like to know what the best battery is? or would you like to prove that RC lipo batteries are the cheapest? Commonly used doesn't mean it's cheaper or most cost effective.
http://www.conhismotor.com/ProductShow.asp?id=43
Heres an example of a cheap lifepo4 battery. its safe, cheap and fairly fool proof. I don't have any lipo experience and i like how safe lifepo4 is. so instead of trying to find a cheap way to make lipo setups safe, why not go with a safer chemistry?
 
senoritoriver said:
It seems like Lifepo4 is best in terms of range, number of recharge cycles etc. but they are fairly expensive. I'm also confused on what you are trying for. Would you like to know what the best battery is? or would you like to prove that RC lipo batteries are the cheapest? Commonly used doesn't mean it's cheaper or most cost effective.
http://www.conhismotor.com/ProductShow.asp?id=43
Heres an example of a cheap lifepo4 battery. its safe, cheap and fairly fool proof. I don't have any lipo experience and i like how safe lifepo4 is. so instead of trying to find a cheap way to make lipo setups safe, why not go with a safer chemistry?

In term of range, lifepo4 is the last one because of its weight. But it is indeed the number one in term of cycle life and calendar life.

It was a thread I started because of the cheap price of the lipo. But now the NMC from Bmsbattery start to challenge the lipo price.

I purchased a lifepo4 from Conhismotor and they delivered me a LiMn2O4 battery.. that has lost 1/3 of its capacity in 6 months. I didn't have a good experience with them.
 
It's true that the cost of lipo has dropped substantially. But the charging setups are still behind. Although in the next few years i see lithium batteries taking a big jump because of things like the nissan leaf.
 
cwah said:
kfong said:
Just get two Hyperions 1420 and network them together. This will give you 24S. The balance taps on rc chargers can detect bad packs easier than you can. Weak cells won't always puff up until it's too late. Balancing your packs will keep them healthy. Hyperions have lots of other features, just go to the Hyperion thread. Bulk charging with such large packs, it's very easy for one cell out of 20 to go out of balance and create a dangerous situation. The larger the packs the more diligent you need to be. I would be implementing any and all saftey methods as possible. We have been seeing a lot of ebike fires over the years and I expect to see a lot more with the increase in user base. Just look at the large number of RC fires should convince you that they will happen. I balance charge every time with my Hyperions, It's very easy with the way I've set it up using a db25 connector for the balance taps. I've posted it on some of my threads. I feel comfortable charging it while in the house doing other things. The charger will fault out if something goes wrong where as a bulk charger will keep on charging, oblivious to any problems.

You can also bulk charge with a set of lipo alarm. That's way cheaper than purchasing 2 hyperion charger + 2 power supply = $300


I bulk charge my 3s lipo with a laptop supply. It always stops at 4.11v per cell. The thing weighs nothing, works perfect. $4 at goodwill. Not that it helps you guys with full voltage packs, but it's great if you want to charge your lipo booster.
 
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