I just received my ST1502-S trimmer today, with the 2.5Ah battery. Should the battery last longer than 20 minutes per full charge?

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Is 20 minutes the expected runtime for this trimmer (ST1502-S) and battery (2.5Ah)?  It's good to get the taller grass trimmed away from the perimeter of the house and touch up a few areas, but seems like a rather short runtime.
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Nathan Oliphant

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Posted 3 years ago

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Blue Angel, Champion

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Nathan, under normal use trimming the consensus seems to be people are getting somewhere between 30-60 minutes of use depending how hard they're pushing the tool and how continuous their workload is.

If you were using it continuously in taller thicker grass I can see a shorter run time.

Did you fully charge the battery fully before use? :-)

I'm not sure if there's any real proof to back this up or not, but I've heard claims that batteries tend to gain a little efficiency after a few charge/discharge cycles. I would try it a few times, especially after you have your taller grass under control, and make a judment call at that time.

Other than the short run time, what did you think of the trimmer?
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Nathan Oliphant

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I charged the battery fully before use.  It was the first use, so it may be that it will improve a little as I use it.  I will give it a good workout this weekend, so hopefully the runtime will improve.  Given a 9.65 acre yard, maybe I need to upgrade to a higher amp-hour battery or two.

Other than the short run time, the trimmer was great!  I am trimming a mix of taller grasses, and the occasional Himalaya blackberry and it rarely bogged down.
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Blue Angel, Champion

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Wow, 9.6 acres? How long do you expect it to take to trim everything?
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Nathan Oliphant

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It depends on how long it takes this trimmer to cut through redwood trees . . . fortunately, I only plan on hitting specific areas with the trimmer (I think I'll trim around the redwoods), so maybe an hour or two a week.  I am currently waiting on a second battery to arrive so that I can swap them out as needed.
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geoff

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Did you charge it when you first opened the package or did you pop the battery right in without charging it first? If you didn't charge it first, that probably explains the short run time. Run time will depend on a variety of factors, including how heavy was the trimming you were doing, the outside temperature and the state of the battery when you began using it. I popped my battery in without charging it and I had a similar experience in terms of run time as you did despite doing heavy duty trimming. Then I recharged it, ( which the instructions tell you to do BEFORE first use but I was impatient). After i recharged it properly, my run time was much longer. In addition, when I opened my spare battery I did put it in the charger before using it and was surprised that it did take a substantial charge. 

Geoff
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Blue Angel, Champion

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Absolutely right!

An Ego pack that sits unused for more than 30 days is automatically discharged to 30% capacity. This is the Long Term Storage mode programmed into the packs, and one of the more advanced features that sets Ego's battery and charger system apart from the competition.

Anyone experiencing a much shorter than expected run time should remember to ask themselves when the last time the pack was charged. If it's been a few weeks this is likely the culprit. :-)
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Nathan Oliphant

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Battery was charged fully before use, then slapped into the trimmer as soon as it was good to go.
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(a)Typical Engineer

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Blue Angel, is the 30% discharge with the battery sitting by itself, or in the charger?  Rapid Charger or Standard Charger (or both)?
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Blue Angel, Champion

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Any battery either sitting alone or in either charger. There's a resistor bank built into the battery's control board for the self discharge operation, during which the end cap of the battery will be warm to the touch.
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Larry

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I got the 5.0 amp battery so I could work until I was tired
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That's the ticket, Larry!
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Don Schultz

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I have the same problem Nathan.  I purchased the trimmer with 2.5AH battery last week and started using it as soon as the battery finished charging.  The first use was intended as a shakedown to confirm all features were functioning properly.  We both agreed that the trimmer performs very well.  However, my wife only got approximately 15-20 minutes of use before it quit.  Hoping it was just a fluke I immediately put the battery back on the charger and then she gave the trimmer another shot about 2-1/2 hours later.  She got the same results again with less than 20 minutes.  I was really curious to test it myself so I took it for a spin yesterday and to trim our 300 ft drive and the entrance I had to recharge twice!  That's 3 full charges to do less than an hours worth of work.  After seeing how well the unit cuts through the weeds and grass I was ready to purchase a second unit.  Home Depot is selling them for about $20 more than a separate battery.  I just don't want to waste the money if the batteries are that impotent.  I am trying to reach EGO for a resolution but their phone network seems ineffective and keeps hanging up on me.
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Another option, Don, is to use a larger ah battery in the string trimmer. The 5 ah might be a better choice for your 300 ft drive. It'll make the string trimmer a bit heavier since the battery is heavier, but could be worth the tradeoff in weight vs time.
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szwoopp, Champion

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And if the weight is an issue there is a battery backpack available

https://egopowerplus.com/collections/power-batteries-chargers/products/ego-power-backpack-link
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Don Schultz

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Thank you for the suggestion Oregon Mike.  I would love to have a 5AH battery but they are very expensive.  I think I'm beginning to understand EGO's marketing strategy.  They are leveraging their products buy selling them at a price point just slightly higher than their individual batteries.  The Chain saw kit is only $80 more than the 5AH battery alone!  It must be working because the products seem to flying off the shelf.
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Don, yeah a lot of companies do that. I needed a replacement battery for my SOB cordless drill and a single battery was basically $100. I was able to buy a new drill that came with 2 batteries, a charger, and a bag to hold it all for $80. Go figure. 
Anyway, maybe there's an EGO product that comes with 5ah battery that you're interested in?
But, yeah, once in awhile we might have to bite the bullet and just buy a battery.
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geoff

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I have several Ego products, two trimmers, handheld blower, backpack blower and snowblower. If you run the low amp battery continuously, 20 mins is about right. Fortunately with all my purchases, I have now three chargers, 3 of the low amp batteries and 3 of the large amp batteries which last at least twice as long. I am very happy with their performance, especially when weighed against the many problems of a gas equivalent. I have at least two batteries charging and two batteries already charged and ready to use. I know you don't have all that and I wouldn't suggest you need to purchase everything I have. On the other hand you mentioned getting a second trimmer and battery and charger. That way you always have a second battery charged and ready to go. Swapping out batteries is a lot quicker than stopping to mix gas and oil and refiling it. 
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Don Schultz

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Thank you for your input geoff.  I understand I can solve the problem by spending more money but part of the allure was the advertised claims of 30-60 minutes of run time and the replacement of gas powered trimmers which run much longer.  If 15-20 minutes is the reality EGO needs to stop claiming otherwise.  On the other hand, I have also seen many reviews where the users claim to get much longer run times which makes me think I have a bad battery.
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szwoopp, Champion

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I think you are correct Don.  The blowers on turbo certainly suck up the power and shorten run time.  I have not heard any such comments regarding the string trimmers.  I could not find anything in the manual, but I am sure someone will post an answer soon.
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Oregon Mike, Champion

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I think the only longer run time comments made by EGO were in conjunction with the larger ah batteries. I could be wrong since I haven't looked at the ads in awhile. I get close to an hour with my 5ah battery in my 21" push (non-sp) mower. It's probably easy for people to over-estimate run times too. I know my string trimmer with 2.5 ah battery probably would only run about 20 minutes or so if I kept it on continuously and at full speed. Since I will trim an area and then turn it off as I move to another area and then turn it back on, it seems like I get longer run time but it's probably only 20 actual  minutes of use. Same with my blower. I rarely use it at full power, turn it off when moving to another spot, etc, it just doesn't need it, so it probably seems I get more run time out of it than what actually happens.
Hmm, seems like a run time experiment is in the offing.
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szwoopp, Champion

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some additional info for inquiring minds


https://community.egopowerplus.com/ego/topics/15-trimmer-run-time?topic-reply-list%5Bsettings%5D%5Bf...
Seems our professional landscapers would have some good input on this question.  Hopefully they will chime in.
(Edited)
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Michael Ross

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Newly purchased String Trimmer with 2.5 Ah battery. Five run-charging times gives about 15 minutes of continuous run time.  I like the machine but the run time is disappointing.  I have a case number and a question into EGO; however, I am not holding my breath.  The manufacturer should be upfront with run time.  Most of us that run trimmers do so continuously and the run times for the battery should be prominently displayed not hidden in a thread like this.  It seems 15 minutes is what my battery run when approaching continuous-run-time while trimming tall grass from the top down into little bits for fire break.     
(Edited)
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15 - 20 minutes sounds about right to me. Especially if you are running full gas on a 2.5 ah battery. A bigger battery will get you more run time. As will not running the trimmer when you aren't actively trimming.