captain stacker

iTrader: (10)

The 4250 I saw at amain had a roar sticker and 7.4v on it.

Do protek offer a lihv version as well as the lipo?

WillS

iTrader: (32)

There is one but its only regulated at Roar races.


8.3.2.5.4 Maximum temperature for a charged li-poly battery pack shall be ambient temperature +/- 5 deg..

8.3.2.5.5 The use of heating devices of any type to heat a li-poly battery is strictly prohibited.

8.3.2.5.6 The use of cooling device and or freeze sprays of any type to cool a li-poly battery is strictly prohibited.

8.3.2.5.7 Overcharging/Overheating is defined as but not limited to the following:

• Charging of a li-poly battery with a charge profile other than CC/CV (i.e.
• NiCad/NiMh)
• Charging at a charge rate higher than 1C
• Charged battery voltage exceeding the max charge voltage per 8.3.2.5.2,
• Heating of the li-poly battery beyond the max. charged temp and or the use of cooling devices to cool an overheated battery per 8.3.2.5.4., 8.3.2.5.5. and 8.3.2.5.6.

Overcharging/Overheating will not be tolerated per section 5.13.10

thecman26

iTrader: (112)

https://www.amainhobbies.com/protek-...102-15/p423775

ROAR approved/Cheater enabled

WillS

iTrader: (32)

Not sure I do know the one they sell now is a LiHV pack.

Link to Protek 4250mah

Has a warning on the description:

Hi-Voltage Capable
This specially formulated battery features LiHV technology which allows the cells to safely reach a higher overall voltage (4.35V per cell vs standard 4.20V per cell). Achieving the higher voltage does require a LiHV capable charger, but the power gains are significant to the overall punch and power for the model. This battery can also charge and function perfectly at typical 2S voltages (8.4V), but please note: cell voltages exceeding 4.20V per cell is prohibited from sanctioned racing rules, such as ROAR, IFMAR, etc.

captain stacker

iTrader: (10)

Ok so most seem to have discounted the saddle lipo out! Personally I'm on the fence.....

Now shorty's.....

4000, 4250, 4500, 5000, 5300.....

Lower mah = lower IR, however
Higher mah = higher average voltage

Now which ones will prove best?

I guess depends on each individual setups!

RC*PHREAK

iTrader: (146)

I'd love to see motor dyno numbers powered by a cooked pack and then the same motor powered by a pack charged at 1C.

mgers75

iTrader: (10)

That's good to know, thanks for clarifying that. I guess its up to the individual track to make there own rules and police. I know it a pain in ass to tech everyone at club races and smaller events. The practice of warm-up cycling lipos hasn't caught on in my region, so I'll stick to charging normally until I feel I'm at a competitive advance.

WillS

iTrader: (32)

That is an incorrect statement.

Mah has nothing to do with internal resistance. Milli-amp hour or commonly referred to as Mah is the batteries ability to store energy equating to run time.

IR or internal resistance is the process in which the battery is made. Chemically and mechanically the internal resistance is all based on the manufacturer tolerances to make the pack.

Only reason I ever ran square, stick or saddles was because it was needed for runtime but that really is not needed now with the better construction of batteries and motors. 17.5 SCT seems to have the highest draining on any battery and was the only class I ran square/saddles in for 17.5 racing.

WillS

iTrader: (32)

This is a great article that explains Lipos

A Guide to Understanding Lipos

Krio

iTrader: (159)

Internal resistance is directly related to the capacity of the pack. Build two packs with identical cells, but give one twice the capacity (mah rating). The pack with the larger capacity will have a lower overall internal resistance (not internal resistance per cell, but overall pack resistance). This is why higher mah packs hold a higher voltage under load.

WillS

iTrader: (32)

Please elaborate on this? Working avionics this goes against everything I was taught and understand about batteries/electronics.

Socket

iTrader: (61)

I've been told the new R1 Wurks black shorty is good. I don't have one yet..it's in the mail, so this is not based on experience.

The protek 4250 is hard to beat. They like to swell, but give amazing numbers through their life span. Usually a battery will last 2 months or so before I give it away to a novice racer. This is the point where IR's get over 2.0 per cell.

I have swollen some huge, and still just tick along fine. I tried t explode a swollen one...

Never phased it. Amain warrantied one that got big on its 4th cycle.

This is for 4.35v racing. For 4.20, protek is still up there, but add in the fantom, graphene, and the ultimate.

A Reedy battery is coming soon.

Socket

iTrader: (61)

The 4250 is roar approved.

40yoCaliRacer

iTrader: (4)

Have you tried Pro Match? They are in AZ.

CTRJ

iTrader: (13)

Socket, i noticed that missing from your list is the Orion (which I have 3 of and are the most popular pack at my track). Do they just not have good IR numbers?