Lipo vs Li-Ion

[djmoose]

I'll end with re-iterating my first point on Safety.

Also, please remember, we're talking about Li-Po packs USED FOR RX power...they'll almost never approach their full C rating in usage.

I agree that Li-Ions are a little safer then Li-Po packs.

That does not automatically make Li-POs more unsafe then they already are.

If you're honestly afraid of using 2S 2200 lipos for Rx power, then by all means, use Li-Ion. Simple as that.

 

[gyro]

Who here would buy a Prius instead of a Tesla if the Tesla was cheaper?

Ok, let's compare a Tesla to a ThunderPower 2S 2200. Thunderpower is an American company and all packs are assembled and tested here in the states.

A ThunderPower Prolite G8 2S 25C 2100mah pack is listed at 29.99. It weighs 3.77 oz. (~.5 oz heaver, ~$9 cheaper, and ~20C more powerful)

The Thunderpower pack is still cheaper, assembled here in the US, is .5 oz heaver, and much more powerful. If there is any American company that I trust C ratings and durability from, it's Thunderpower.

I won't bother doing another numbers to numbers comparison with the new cars and Thunderpower packs on this site because a site sponsor can just write it off as "simple napkin calculations" (even though the Prius vs Tesla comparison proves my point even further...but I'll let the readers decide that)

I'll take the "Tesla" any day of the week and will heed the responsibility of caring for it correctly. Enjoy the Prius if you so choose.

Moose, didn't you mean to compare identical capacities? The Fromeco ReLion packs are 2600mah, and thus the 2100mah Thunderpower wouldn't be equivalent... however the Thunderpower G8 2s 2700mah (much closer in size at 100mah difference in capacity, instead of 500mah) specs are as from: http://www.thunderpowerrc.com/2700-mAh_2/TP2700-2SPP25

The 2s 2700mah G8 pack is 123g, compared to 93g for the ReLion 2600mah, and the price is 39.99 compared to the ReLion at $38.00 with deans and balance tap. Not sure I see a weight or price advantage here, however as you correctly state, the Thunderpower are more powerfully rated.

As I've said previously, I use BOTH chemistry types currently, ReLions in my 92" Edge, and LiPos in my 30cc planes, so I'm happy to use either based on application.

 

[djmoose]

Moose, didn't you mean to compare identical capacities? The Fromeco ReLion packs are 2600mah, and thus the 2100mah Thunderpower wouldn't be equivalent... however the Thunderpower G8 2s 2700mah (much closer in size at 100mah difference in capacity, instead of 500mah) specs are as from: http://www.thunderpowerrc.com/2700-mAh_2/TP2700-2SPP25

The 2s 2700mah G8 pack is 123g, compared to 93g for the ReLion 2600mah, and the price is 39.99 compared to the ReLion at $38.00 with deans and balance tap. Not sure I see a weight or price advantage here, however as you correctly state, the Thunderpower are more powerfully rated.

As I've said previously, I use BOTH chemistry types currently, ReLions in my 92" Edge, and LiPos in my 30cc planes, so I'm happy to use either based on application.

I was going by Fromeco's "Usable Capacity" rating of their 2600 which is 2300. But, I'll agree.

It costs two dollars more, weighs 1.4oz more, and has ~20C more power.

I will trade 1.4oz (more like 3oz in a 50-60cc plane) and $2 for ~20C more power.


It really doesn't matter what packs you use...

 

[gyro]

I was going by Fromeco's "Usable Capacity" rating of their 2600 which is 2300. But, I'll agree.

It costs two dollars more, weighs 1.4oz more, and has ~20C more power.

I will trade 1.4oz (more like 3oz in a 50-60cc plane) and $2 for ~20C more power.


It really doesn't matter what packs you use...

You're right, it doesn't. I'm trying to remain neutral in my advocacy, and stay with facts, which is why I explained that. Since I fly with both, I promote both, and think both work perfectly for 3D flying in all cases.

Well, you mentioned that you don't run your LiPos down entirely, and neither do I. I follow the general rule I've read about online to "leave in 20%"
Which, in a 2700mah LiPo's case, would be about 2160mah, which is still less than Fromeco's 2300mah "Usable Capacity" (which for math purposes is 88% of published total capacity)

You mentioned stopping at 3.8v per cell, which I think is closer to 30-35% of capacity, right?

 

[Fromeco]

Nowhere in my post did I state that Polymers were unsafe. I only stated that Lithium Ions were safer, because they actually are. They have built in engineering controls that make them mathematically safer than a Lithium Polymer. I was very careful to not say that Polymers were unsafe. To be clear Fromeco is not making the statement that Polymers are unsafe. This is much like a Glock and a 1911-45. The Glock has a single trigger safety, the 1911 has a button safety and a beaver tail grip safety, is the Glock unsafe? No, the 1911 is just safer. Guns like batteries are tools, devices, appliances that provide a service and only do what you tell them to do.


The Tesla analogy was only used to state that Tesla uses cylindrical cells much like ours. They do this because they are safer, their outcomes are more easily controlled with engineering controls.


Using Thunderpower as competitive example is good. Thunderpower makes good packs, they make them here!!! And their cells have provenance.


The 8Ball is a tool of convenience. Just like a gas gauge in a car. We all know how big our tanks are, we could fill up, drive 10 miles, and do the calculations. Do we have to have a gas gauge? No, it is a matter of convenience I wouldn’t call it “a Band Aid for a battery chemistry that needs it”. There are a lot of pilots that really don’t want to get into the details of electricity, there are a lot of people that can’t get their heads around electrical theory . They want to plug into a battery and see a result, without doing any calculations. NOTE: We designed the 8Ball specifically for our packs. It can be used on a Lithium Polymer as long as it is 2S. As far as “THE SAFEST” method, that is a matter of opinion. The process will work as described. Fromeco will always recommend a Load Checker to check RX flight packs, Lithium Ion or Lithium Polymer, and it doesn’t have to be an 8Ball, and they do not have to be our batteries.





Kurt Cook
Fromeco Scale Avionics LLC

 

[3dmike]

Nowhere in my post did I state that Polymers were unsafe. I only stated that Lithium Ions were safer, because they actually are. They have built in engineering controls that make them mathematically safer than a Lithium Polymer. I was very careful to not say that Polymers were unsafe. To be clear Fromeco is not making the statement that Polymers are unsafe. This is much like a Glock and a 1911-45. The Glock has a single trigger safety, the 1911 has a button safety and a beaver tail grip safety, is the Glock unsafe? No, the 1911 is just safer. Guns like batteries are tools, devices, appliances that provide a service and only do what you tell them to do.


The Tesla analogy was only used to state that Tesla uses cylindrical cells much like ours. They do this because they are safer, their outcomes are more easily controlled with engineering controls.


Using Thunderpower as competitive example is good. Thunderpower makes good packs, they make them here!!! And their cells have provenance.


The 8Ball is a tool of convenience. Just like a gas gauge in a car. We all know how big our tanks are, we could fill up, drive 10 miles, and do the calculations. Do we have to have a gas gauge? No, it is a matter of convenience I wouldn’t call it “a Band Aid for a battery chemistry that needs it”. There are a lot of pilots that really don’t want to get into the details of electricity, there are a lot of people that can’t get their heads around electrical theory . They want to plug into a battery and see a result, without doing any calculations. NOTE: We designed the 8Ball specifically for our packs. It can be used on a Lithium Polymer as long as it is 2S. As far as “THE SAFEST” method, that is a matter of opinion. The process will work as described. Fromeco will always recommend a Load Checker to check RX flight packs, Lithium Ion or Lithium Polymer, and it doesn’t have to be an 8Ball, and they do not have to be our batteries.

View attachment 20841



Kurt Cook
Fromeco Scale Avionics LLC

I commented on the article on the front page but also wanted to comment regarding the 8Ball.... I own it... I love it... and yep I'm too busy to even care about doing the calculation. I grab the 8Ball and bam.... I know then if I am good or not. Easy Peazy!

Thanks Kurt!

 

[abobo808813]

Nowhere in my post did I state that Polymers were unsafe. I only stated that Lithium Ions were safer, because they actually are. They have built in engineering controls that make them mathematically safer than a Lithium Polymer. I was very careful to not say that Polymers were unsafe. To be clear Fromeco is not making the statement that Polymers are unsafe. This is much like a Glock and a 1911-45. The Glock has a single trigger safety, the 1911 has a button safety and a beaver tail grip safety, is the Glock unsafe? No, the 1911 is just safer. Guns like batteries are tools, devices, appliances that provide a service and only do what you tell them to do.


The Tesla analogy was only used to state that Tesla uses cylindrical cells much like ours. They do this because they are safer, their outcomes are more easily controlled with engineering controls.


Using Thunderpower as competitive example is good. Thunderpower makes good packs, they make them here!!! And their cells have provenance.


The 8Ball is a tool of convenience. Just like a gas gauge in a car. We all know how big our tanks are, we could fill up, drive 10 miles, and do the calculations. Do we have to have a gas gauge? No, it is a matter of convenience I wouldn’t call it “a Band Aid for a battery chemistry that needs itâ€. There are a lot of pilots that really don’t want to get into the details of electricity, there are a lot of people that can’t get their heads around electrical theory . They want to plug into a battery and see a result, without doing any calculations. NOTE: We designed the 8Ball specifically for our packs. It can be used on a Lithium Polymer as long as it is 2S. As far as “THE SAFEST†method, that is a matter of opinion. The process will work as described. Fromeco will always recommend a Load Checker to check RX flight packs, Lithium Ion or Lithium Polymer, and it doesn’t have to be an 8Ball, and they do not have to be our batteries.

View attachment 20841



Kurt Cook
Fromeco Scale Avionics LLC

Nowhere in my post did I state that Polymers were unsafe .Well whats this say ?

 

[gyro]

View attachment 20875
Nowhere in my post did I state that Polymers were unsafe .Well whats this say ?

I personally added that picture when I promoted Kurt's post to an article. (all the pictures, actually). I did this because:

1- I felt it was coherent to that paragraph about how Li-Ions vent fire in a controlled manner after the other fail-safe protections are exhausted, whereas LiPos don't have any safety features and burn more violently.

2- articles full of text with no pictures aren't as interesting.

Sorry that gave you the wrong impression.

 

[njswede]

Enjoy your 8-ball load testers. My comment about possibly using an 8-ball on Li-Po packs was kind of round-about. I wanted people to realize that you don't NEED to load test Lipos. My no fly voltage is 3.8V per cell. DONE. no funny load testing. No chances taken.

In FACT...if you want the to know "THE SAFEST" way to keep track of your rx packs? (either chemistry) Here's a little procedure that is bulletproof if you're not too lazy.

1. New Rx pack...fully charged...any chemistry
2. Fly 1 normal/typical flight
3. Charge pack(s) and record how much went back into them.
4. Divide total pack capacity by how much your put back in, round down, and subtract one.
5. Use this number (total number of flights you can fly on a charge) ALONG with measuring voltage in between flights and you won't have a problem.
6. Each time you fully recharge your packs, keep track of how much mah you put back in. If this number starts to very, replace packs.
7. Buy new rx packs every 2 years. (same recommendation as Fromeco)

In my honest opinion, the 8-ball load checker is a band-aid for a battery chemistry that needs it.

I'm not sure I agree that's the safest method, Moose. You're basically assuming the battery is useful all the way down to full discharge and subtract a single safety flight from that. I would personally add more margin of error than that.

 

[cardenflyer]

Not really part of the discussion but thunder power is buy one get one free of their g4 lipos! Until Feb 7. I think I'll try a set of 3300 in my 104". Can't beat 2 TP 3300 2s lipos shipped for $21!