How to get the most "umph" out of lipos

[marshmallow]

Hi guys, just wondering if anyone has any tips or tricks on how to get the most "umph" out of lipos. I have seen people charging at stupid amps like 20 for example, does this effect the output of the lipo? I have seen other people having to run there cars down before a 12th scale final because they have more than the BRCA voltage allowed before a final. Is this just for safety or will more voltage increase the power?

[mattybucks]

Hi guys, just wondering if anyone has any tips or tricks on how to get the most "umph" out of lipos. I have seen people charging at stupid amps like 20 for example, does this effect the output of the lipo? I have seen other people having to run there cars down before a 12th scale final because they have more than the BRCA voltage allowed before a final. Is this just for safety or will more voltage increase the power?

Crazy - it's always the stock classes that abuse cells to try and to gain an advantage. With modified the motors are quick enough too quick in fact.

Charge at a safe level, the rules are there for a reason.

[Suzukitudor]

Neil lipos are massively potent power supply units with a huge amount of capacity for holding power, far more so than the cells of old. But they need to be treated with respect. That's why we have rules like charging in fire proof bags and recommended charge rates. Ignore the idiots ramping up cells and work on clean lines, consistency, car setup, and racecraft if you what to get ahead.

[SlowOne]

My tips for getting the best from your LiPos...

Store above 10degC, not outside and never below 0degC.
Store at about 50% charge, never flat and never fully charged.
Charge at 1C in a kevlar-lined bag with the flap firmly closed
Discharge at 1C in a kevlar-lined bag... etc.

At the first sign of any puffing, the cell will continue to operate but performance will be low. Currently I am using VapexTech cells which are excellent and cheap to replace, but one only three meetings old has already dropped its performance. Replacements on the way!

The biggest risk is when people charge LiPos above 4.2v per cell. That's why we have rules for that and that's why we check it. There is a performance advantage, but you're seeing the wrong thing by quoting the 12th scale guys.

The reality is that every charger is different and some will charge to 4.21v or 4.22v. What we are checking at 12th events is that cells are at 4.20v or less before cars go onto the track. To lose that .01/.01v the easy thing to do is rev the motor up, and that's what you see.

I race with people who use high charge and discharge rates on cells and they are rarely faster than me on top speed or acceleration out of a corner. A good quality, low IR cell will give you more than any amount of abuse through charging and discharging. HTH :)

[marshmallow]

I was just a little confused having seen and heard a lot of different things regarding charging lipos etc. I have used them for years from natinal to club meetings. Just wanted to see if there was any alternative way of charging to get more performance out of your lipos.

[neallewis]

I was just a little confused having seen and heard a lot of different things regarding charging lipos etc. I have used them for years from natinal to club meetings. Just wanted to see if there was any alternative way of charging to get more performance out of your lipos.

If you think you need to get more "umph" out of your lipos, its probably time to replace them with some new ones. Trying to push old cells is a bad idea.

[Dr Fly]

I test LiPos as part of my work and i can confirm that there are a couple of ways of squeezing an extra couple of watts out of your batteries when you are at max throttle. but the performance increase is absolutely marginal and never worth it. Only the best drivers will notice any difference. The downside is that you will prematurely age your battery, this means the internal resistance of your cells will increase at a quicker rate than normal as the battery ages, which results in less "umph" than people who look after their cells

As for charging the cell to above 4.2v, this will give you a tiny amount of time where you can draw more wattage (probably your warm up lap), but again, it will really age the cell, and you will get very little advantage for it.

I can understand people trying to get the most out of every part of the car, but the best way to get the best performance out of a battery is to care for it and treat it will. I have seen far more top racers lose places because there batteries are not looked after very well, than i have ever seen from anyone who tries to squeeze out every last drop of power from the cell.

So as others have said, treat your cells well, and they will never let you down :p

[/tobys]

Most people in buggy run a couple of warm-up/installation laps before the start of each run anyway - surely negating the effects of overcharging, which brings in unnecessary risk IMO.

[ishiba]

One option for storing lipos is at 3.4 volts/cell in refrigerator (0-5 degC). Works well for storing lipos for several months.

[4nd7]

Most people in buggy run a couple of warm-up/installation laps before the start of each run anyway - surely negating the effects of overcharging, which brings in unnecessary risk IMO.

What this man says. Restrict your warm up lap to one if you have to do any at all and if you run a class when you need to bring tyres in just potter around at half throttle and maintain cornering speed to scrub tyres.

I like seeing people doing 3/4/5 laps warm up because i know i'm going to gain 2 meters on them off the grid straight away.