Charging rate ??

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Old 09-30-2015, 02:19 AM
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Default Charging rate ??

Is there a performance gain to charging your lipos at a higher amp ?? or is it just to charge faster ??
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Old 09-30-2015, 02:34 AM
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I don't think the average joe will notice any difference. I prefer to keep my LiPo's running for a while instead of destroying them after 1 day.

So, the stock boys will probably tell you : "Yes, we notice the difference". The modified (the cool guys) will say : "No you won't". I agree (we only race mod over here) with the mod guys. You won't notice. If you want a longer lasting LiPo then charge at max 2C. I, personally, only charge at 1C. Never have any problems. I plan to keep it that way.
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Old 09-30-2015, 02:48 AM
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Originally Posted by dennisV View Post
I don't think the average joe will notice any difference. I prefer to keep my LiPo's running for a while instead of destroying them after 1 day.

So, the stock boys will probably tell you : "Yes, we notice the difference". The modified (the cool guys) will say : "No you won't". I agree (we only race mod over here) with the mod guys. You won't notice. If you want a longer lasting LiPo then charge at max 2C. I, personally, only charge at 1C. Never have any problems. I plan to keep it that way.
thanks for the reply. I only ever charge at 1c but have heard Jason Snyder mentioning a cpl times people charging at 40 amps was just wondering if there was a real reason other than time lol.
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Old 09-30-2015, 07:00 AM
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IMO, if you are in problems with getting your battery charged up, get an extra battery. Problem solved.
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Old 09-30-2015, 07:43 AM
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If you couple a high discharge rate with a high charge rate (40amps+) and are running a 17.5/13.5 class, there is a noticeable gain in performance. Huge gain, no. Noticeable, yes. Is that gain worth the effort and expense if you can't make a CLEAN marshal free run, NO.
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Old 09-30-2015, 09:16 AM
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Couple of different thoughts here,

More importantly a case of different applications/usages.

For mod, you'd typically not need to charge at super high amp rates. Charging at 2c or slightly above maybe needed if your just trying to get your LiPo's charged faster, as the higher the amp rate, the quicker the charge time will be. I'd say most mod racers will stay around a 1 or 2c charge rate, which isn't a bad thing. Only down side is the ir of the packs will get higher over time, but you'd likely not really notice it for a long time. And unless you have a charger that can show what the ir (internal resistance) of the pack is or isn't, you won't be able to know anyway.

For stock, it's a bit of a different world. One that has ton of opinions as to why you'd even need or not need to charge at high amp rates. As with most things in the world of stock racing, if you're trying to be at the very top, every little thing counts. LiPo's are no exception in this case. You're trying or pushing every last bit of performance out of the whole package. So the charge rate, discharging, cycling prior to running, newness of the LiPo, grade of LiPo (read the "C" rating of the LiPo for what it's worth), size of wire, and such all matter to a degree. For most club racers, it's likely not going to be a deal breaker if they aren't charging at high amp rate or doing a lot of things some stock racers do to get that edge over everyone else. However it is a monkey see, monkey do type thing, so many will do things simply because they saw or heard that something works, which may or may not always be the right way.

Most of the newer gen of LiPo batteries out now can easily handle a 10-15a charge rate (which a lot of times is right around the 2c rate) without much issue. It seems that with every new gen of LiPo that comes out, that part does get better than the gen before. It seems that the dirt oval racers can be given some credit for the high amp charge rates for certain stock classes, as it seem they have been doing it a while. They just might be on to something as I know of at least one Mfg. that is or has a HV LiPo coming out and I'm sure there will likely be others that follow suit. However for sanctioned racing such as ROAR and IFMAR, high amp charge rates aren't allowed to begin with, so much of this is fairly moot. Although right after the on road Nats this year, a little vid was done using the same car, same driver, same track on the same day, and all that was changed was the charge rate of the LiPo from 5-6a (1c) to 40a and their results were rather interesting.

Does charging at a high amp rate degrade the LiPo's faster? Opinions say both depending on who is asked. While not a huge fan of high amp charging, I have done the 30-35 amp charge/discharge of my LiPo's that I was using for stock racing and I hadn't really noticed any huge LiPo degrading over the 9-10 months of doing so. I did notice that sometimes the extra voltage, punch, or whatever I might have gained in charging at a high amp rate was usually lost in my first few mistakes on the track and there were times I would actually turn my fastest lap times at the end of a practice session (about 10-12 minutes of running) when the LiPo didn't have all the punch and power. Funny how that works.

In the end, it's the racers call wether or not they want or need to charge at high amp rates for the given application they are racing. Mod, likely not. Stock, it is a possibility that it may have to be considered and in the right conditions, could show favorable results, but could,come at a cost too. I think a higher amp discharge (if a racer has a charger that will do a high amp discharge) and normal charge rate (1c up to 10-15a) could be the best way to go about things if you can keep the pack warm (not hot) during the charge. Doing that may give a better result over a longer time frame with less potential issues.

As always, use caution and in some cases extreme caution when charging or charging at high amp rates. Things can and do go wrong, and the results of that can be catastrophic. If in doubt, don't do it. If you're ok with the idea, be sure you have done everything you can to do so as safely as possible. The risk/reward may not be worth it.
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Old 09-30-2015, 09:56 AM
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Yes, it degrades lipos much faster when you're discharging to 2.90 at 40 amps, then charging at 70 amps to 4.35. Usually get 4 weeks out of a single battery.
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Old 09-30-2015, 10:02 AM
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Originally Posted by racer1812 View Post
If you couple a high discharge rate with a high charge rate (40amps+) and are running a 17.5/13.5 class, there is a noticeable gain in performance. Huge gain, no. Noticeable, yes. Is that gain worth the effort and expense if you can't make a CLEAN marshal free run, NO.
I also noticed a huge different charging at 22.5 amps (max charge rate on the Orion 4500 lipo is 5C), and when I could only charge at 10 amps. Was able to make triples in stock with the higher charge rate I wouldn't have even bothered trying at 2C, and a noticeable punch increase. So its 22.5 amps for me in stock. In anything else 13.5 22.5 as well. Wheeler gets 2C, 9 amps.
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Old 09-30-2015, 10:04 AM
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Originally Posted by Teufel Racing View Post
Couple of different thoughts here,

More importantly a case of different applications/usages.

For mod, you'd typically not need to charge at super high amp rates. Charging at 2c or slightly above maybe needed if your just trying to get your LiPo's charged faster, as the higher the amp rate, the quicker the charge time will be. I'd say most mod racers will stay around a 1 or 2c charge rate, which isn't a bad thing. Only down side is the ir of the packs will get higher over time, but you'd likely not really notice it for a long time. And unless you have a charger that can show what the ir (internal resistance) of the pack is or isn't, you won't be able to know anyway.

For stock, it's a bit of a different world. One that has ton of opinions as to why you'd even need or not need to charge at high amp rates. As with most things in the world of stock racing, if you're trying to be at the very top, every little thing counts. LiPo's are no exception in this case. You're trying or pushing every last bit of performance out of the whole package. So the charge rate, discharging, cycling prior to running, newness of the LiPo, grade of LiPo (read the "C" rating of the LiPo for what it's worth), size of wire, and such all matter to a degree. For most club racers, it's likely not going to be a deal breaker if they aren't charging at high amp rate or doing a lot of things some stock racers do to get that edge over everyone else. However it is a monkey see, monkey do type thing, so many will do things simply because they saw or heard that something works, which may or may not always be the right way.

Most of the newer gen of LiPo batteries out now can easily handle a 10-15a charge rate (which a lot of times is right around the 2c rate) without much issue. It seems that with every new gen of LiPo that comes out, that part does get better than the gen before. It seems that the dirt oval racers can be given some credit for the high amp charge rates for certain stock classes, as it seem they have been doing it a while. They just might be on to something as I know of at least one Mfg. that is or has a HV LiPo coming out and I'm sure there will likely be others that follow suit. However for sanctioned racing such as ROAR and IFMAR, high amp charge rates aren't allowed to begin with, so much of this is fairly moot. Although right after the on road Nats this year, a little vid was done using the same car, same driver, same track on the same day, and all that was changed was the charge rate of the LiPo from 5-6a (1c) to 40a and their results were rather interesting.

Does charging at a high amp rate degrade the LiPo's faster? Opinions say both depending on who is asked. While not a huge fan of high amp charging, I have done the 30-35 amp charge/discharge of my LiPo's that I was using for stock racing and I hadn't really noticed any huge LiPo degrading over the 9-10 months of doing so. I did notice that sometimes the extra voltage, punch, or whatever I might have gained in charging at a high amp rate was usually lost in my first few mistakes on the track and there were times I would actually turn my fastest lap times at the end of a practice session (about 10-12 minutes of running) when the LiPo didn't have all the punch and power. Funny how that works.

In the end, it's the racers call wether or not they want or need to charge at high amp rates for the given application they are racing. Mod, likely not. Stock, it is a possibility that it may have to be considered and in the right conditions, could show favorable results, but could,come at a cost too. I think a higher amp discharge (if a racer has a charger that will do a high amp discharge) and normal charge rate (1c up to 10-15a) could be the best way to go about things if you can keep the pack warm (not hot) during the charge. Doing that may give a better result over a longer time frame with less potential issues.

As always, use caution and in some cases extreme caution when charging or charging at high amp rates. Things can and do go wrong, and the results of that can be catastrophic. If in doubt, don't do it. If you're ok with the idea, be sure you have done everything you can to do so as safely as possible. The risk/reward may not be worth it.
Like dont use a crap charger.
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Old 09-30-2015, 10:40 AM
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As I have heard it... the high charge rate just heats the pack up which changes the way the chemistry runs in the pack. You can get the same small gain with a heating pad and a fresh slow charge if that is indeed the case.
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Old 09-30-2015, 11:06 AM
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Originally Posted by lbenton View Post
As I have heard it... the high charge rate just heats the pack up which changes the way the chemistry runs in the pack. You can get the same small gain with a heating pad and a fresh slow charge if that is indeed the case.
+1!
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Old 09-30-2015, 11:43 AM
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Originally Posted by jpcopeland1 View Post
Like dont use a crap charger.
That too,

Lots of factors to keep track of if people want to go with a high charge rate, quality charger is but one factor
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Old 09-30-2015, 12:16 PM
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I've been charging at 3-4c for the last 3 years. I'll never go back to 1-2c especially on practice days.
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Old 09-30-2015, 12:18 PM
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Originally Posted by lbenton View Post
You can get the same small gain with a heating pad and a fresh slow charge if that is indeed the case.
Most places don't allow that practice of heating.
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Old 09-30-2015, 01:29 PM
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Originally Posted by Andy Koback View Post
Most places don't allow that practice of heating.
They probably don't allow charging at 40 amps or over 8.4v either. Both of which are a lot more dangerous than heating the pack up a little.
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