+Famous.Five Posted November 17, 2008 Share Posted November 17, 2008 Was out yesterday, over birmingham way and decided to get some cache's done, and despite having some brand new rechargables in my oregon 300 the batteries only lasted a few hours !!! AND i'd fogotten to bring spares !! so what's the best make ? does it make a difference which charger you use ? I'm using 'FAMEART' batteries and charger, and am not particularly impressed Quote Link to comment
Garmin8888 Posted November 17, 2008 Share Posted November 17, 2008 Get Uniross ( the black and silver one) off Ebay I use 2500 mah Quote Link to comment
+Bob Smith Posted November 17, 2008 Share Posted November 17, 2008 My Garmin 60 has a set up for the type of battery. if it's set for normal alkaline and you use rechargeables it will indicate a flat state prematurely Quote Link to comment
+Gushoneybun Posted November 17, 2008 Share Posted November 17, 2008 Make sure your Colorado (or any other GPS) is set to the right type of batteries, I use 2650 Duracells and Everready 2700 both work well and give me a good day of caching per pair, or several days on and off. I do not have my Colorado with me but to change battery type look in the setup option. Post on here if you can not see how to change it and I will check later unless someone beats me to it Do not bother with low mah batteries low ones have no chance. Quote Link to comment
+purple_pineapple Posted November 17, 2008 Share Posted November 17, 2008 i';m glad someone asked this question! I'm using 2800mA 7 day shop batteries, and don't seem to charge very well with the 7dayshop charger, but when we borrowed one from MrsPP's work, it appeared to be a lot better. I'm now pondering getting a new, better charger. Quote Link to comment
+HazelS Posted November 17, 2008 Share Posted November 17, 2008 I always used rechargables, and I could get a good days caching out of a set of 2300's. You just have to be strict with yourself over recharging! I've actually given up on rechargables now - I use duracell high powered type pnes for the camera and then when they run out in the camera, I put them into the GPS! I can generally get a good few days caching out of them after that! Quote Link to comment
+Fuchsiamagic Posted November 17, 2008 Share Posted November 17, 2008 I got some 2500 mAh rechargables from B&Q about two weeks ago and GPSr still shows a full charge, even after daily use with the backlight on. Quote Link to comment
+hiho9 Posted November 17, 2008 Share Posted November 17, 2008 jessops branded 2000mah with a jessops charger last me a good 12 hours. Quote Link to comment
Izzy and the Lizard King Posted November 17, 2008 Share Posted November 17, 2008 Uniross 2500mAh give us 16-18 hrs of constant use with GPSMap 60Csx including a few hours of night caching with the backlight on. This is the pack we got over 2 years ago and they are still going strong - as good as the day we got them! With superfast AC and in-car adaptor (not that it should be needed) supplied - an excellent buy. Paul Quote Link to comment
+careygang Posted November 17, 2008 Share Posted November 17, 2008 Everyone so far has been mentioning the capacity of what you are using, but don't forget the type. For quite a while rechargeable batteries were NiCd, the better ones on the market are now NiMH. I do believe that NiCd are now banned for sale in the EU (apart from certain industries, like medical applications) due to their Cadmium content, but whether that legislation has got down to all the market retail outlets I have no idea. However, the cheaper the battery/charger combination, the sooner the batteries are going to be exhausted by poor charging. Rechargables are a complex combination of capacity and charge rate, so my advice would be stick to the decent makes, they'll last longer. Also, don't buy some new NiMH batteries and then use them with an old charger that was designed for NiCd, again it will be a miss-match and the NiMH will be ruined by the wrong charge rate. Quote Link to comment
Izzy and the Lizard King Posted November 17, 2008 Share Posted November 17, 2008 Uniross 2500mAh give us 16-18 hrs of constant use with GPSMap 60Csx including a few hours of night caching with the backlight on. This is the pack we got over 2 years ago and they are still going strong - as good as the day we got them! With superfast AC and in-car adaptor (not that it should be needed) supplied - an excellent buy. Paul These are NiMH supplied with the correct type of charger Quote Link to comment
lakeuk Posted November 17, 2008 Share Posted November 17, 2008 In my gps I use what ever NiMH rechargables are available ranging from 2100 to 2700mAh. For my digital camera I use a set of Sony CycleEnergy 2000mAh which although they have a lower mAh than regular rechargables they have the benefit of a very low self discharge rate so I can leave a set in the camera and also has a spare set in the case for long periods without use and not have to worry about having dead batteries when required in x mths time Quote Link to comment
+PopUpPirate Posted November 17, 2008 Share Posted November 17, 2008 I use IKEA throwaways. Just googled and they get a decent writeup... http://homepage.ntlworld.com/tim.sneller/battery.htm 10 for a quid, bargain! Quote Link to comment
+The Bongtwashes Posted November 17, 2008 Share Posted November 17, 2008 I've got a variety of different NiMH rechargeables, Duracell 2300mAh, Uniross 2000mAh and RS 2600mAh, and a Kodak NiMH/NiCd battery charger, all were paid for by previous employers (Who said 'Cheapskate'? ). I find little difference in performance between the Duracell and RS ones, and usually just use the Uniross ones for emergency, unfortunately this means they have usually lost their charge by this time . Quote Link to comment
andynelaine Posted November 18, 2008 Share Posted November 18, 2008 I use Uniross 2700 rechargables as Elaine brought them for the dig camera but they seem to have landed in our Garmin!! We also have a incar charger so if we are away from home we can always have fresh batteries. Heres Andys nerdy tip of the day.....Maplins(or several other quality electrical stores) sell AA cell holders that are good for 4 batteries!! (about £4 for 3)This little holder has helped me locate my batteries in seconds instead of looking for ages at the bottom of me bag!! Really usfull when you get the dreaded low bat sign at night!! And you can easily keep the dead batteries away from the good ones!! I couldnt say how long they last but without backlight it has found about 30 caches between charges. Andy Quote Link to comment
+Famous.Five Posted November 18, 2008 Author Share Posted November 18, 2008 Sorry, but 2000, 2500, 2700 ? what's the difference ? on these fameart they say (in very small print) Ni-Mh 1.2v mha and 2300 is this supposed to relate to power ? recharge time ? capacity ? Quote Link to comment
+sTeamTraen Posted November 19, 2008 Share Posted November 19, 2008 (edited) Sorry, but 2000, 2500, 2700 ? what's the difference ? on these fameart they say (in very small print) Ni-Mh 1.2v mha and 2300 is this supposed to relate to power ? recharge time ? capacity ? I presume you mean 1.2v and 2300mAh. That means in theory you can draw 2300 milliamps of current from the battery for an hour. Batteries are rated in (milli)amp-hours (electrical charge) rather than watt-hours (energy) because the relationship between the two is the voltage and that's pretty much fixed (once you disregard things like the internal resistance). All NiMH cells run at 1.2 volts - alkaline batteries run at 1.5, so NiMH can give problems if your device needs 1.5 (but fortunately, Garmin thought of that). The different mAh ratings won't make a difference to the "power" of the battery (defined as how much energy you can get out of them per second). If it was a car, you'd be giving it a bigger fuel tank, not a bigger engine. You can choose to buy the biggest capacity rechargeable batteries, although these will probably cost quite a bit more because they'll be the leading brand and you have to pay for their advertising, or the medium ones which may have the best price/performance, or the cheapest ones for the smallest cash outlay. They will all work identically, but the 2700 mAh ones will run your Oregon for an hour or two more than the 2000 mAh ones. Edited November 19, 2008 by sTeamTraen Quote Link to comment
+Eclectic Penguin Posted November 20, 2008 Share Posted November 20, 2008 I've found that battery capacity can vary by quite a bit even if you buy the same brand and same stated capacity in different batches. This is true for well known brands as well as lesser known ones, though I suspect the lesser known brands may vary more... Earlier on this year I bought a batch of 2700MAh batteries from Lidl- they were extremely cheap for the price so I didn't expect much, but were some of the best batteries for capacity I've bought - as with these shops, by the time I went back for more, they were gone. Then, a couple of months later they re-appeared, same capacity but slightly different colour on the packaging. I bought loads based on the previous purchase. The new ones hower were some of the lowest capacity rechargeables I've ever had - in the end I threw many of them away (recycled) as they barely lasted 3-4 hours in my GPSr and my rapid charger refused to even charge the AAA variety. Now, this could have been a rogue batch, but it does illustrate that you can't believe what's written on the battery. I came across an excellent article on the web a while back where someone said that it's best to test each individual battery on its own, whatever the brand/batch and then pair up ones that closely match each other in capacity for best value and duration since the capacity is only as good as the weakest battery in use. As a part of this article they outlined the design of a simple testing device they'd created using an analogue wrist-watch, and a resistor connected across the battery terminals to rapidly discharge and measure the time it takes to completely discharge a fully charged battery - I wish I could find it now as I'd like to construct one of these. Basically, you set the watch at 12 o clock and then attached the battery. The watch would then stop when the battery was fully discharged - times of between 2 hours and 6 hours were measured on similar batteries, consistently per battery. Quote Link to comment
+Guanajuato Posted November 20, 2008 Share Posted November 20, 2008 ... they outlined the design of a simple testing device they'd created using an analogue wrist-watch, and a resistor connected across the battery terminals to rapidly discharge and measure the time it takes to completely discharge a fully charged battery - I wish I could find it now ... Is this what you are referring to? Sounds like an excellent idea! Quote Link to comment
Iwuzere Posted November 20, 2008 Share Posted November 20, 2008 I use high capacity 7dayshop ones if I'm charging them immediately before leaving the house to go cacheing, otherwise the newer Eneloop type (that don't lose charge so quickly sitting around doing nothing) make a lot of sense. I recently switched something on after many months, expecting it to be dead, and was surprised to find it was as right as rain. I looked to see which of my rechargebles were in it, and it was the Panasonic "infiniums". They really do hold their charge longer. Excellent stuff. They might have a smaller mAH number on them, but after a few days sitting around, the so-called 2800s will probably be closer to 2300 anyway (and after a few tens of charges and associated heat damage they'll be nowhere near 2800 any more). A week or two later the 2800s will be close to useless while the low-self-discharge ones will be as fresh as a daisy wearing deodorant Quote Link to comment
+Pharisee Posted November 20, 2008 Share Posted November 20, 2008 I presume you mean 1.2v and 2300mAh. That means in theory you can draw 2300 milliamps of current from the battery for an hour. The quoted 'capacity' is only valid at a specific discharge rate and that rate isn't usually quoted by the manufacturer (it usually is for lead/acid car batteries). If you discharge a fully charged 2300mAh 'AA' battery at a continuous 2.3 amps you'll be lucky if it lasts 15 minutes, let alone an hour and it'll get so hot you can't handle it. The 'actual capacity' will rise as the discharge current drops until it peaks at whatever current is the optimum for that particular cell. As the discharge current continues to decrease and the discharge time increases, then the internal resistance and the 'self discharge' (for lack of a better description) will have an increasingly bigger effect and the actual capacity start to drop again. The optimum discharge rate will vary slightly between different cells from the same manufacturer and will very likely vary to a greater degree between different manufacturers. I have no idea what current the typical GPRs draws but it's unlikely to be exactly on the battery's optimum so the 'checking and matching' mentioned in previous posts is a good idea... if you can be bothered to do a bit of 'science-ing about'. A pair with the same discharge characteristics and with an optimum discharge rate that's close to whatever your GPSr draws will give you the longest duration. Quote Link to comment
+PopUpPirate Posted November 20, 2008 Share Posted November 20, 2008 I always think of it as being like a jug of Tropicana. A 2800ml will last twice as long as a 1400ml bottle, cos it has twice as much "juice" in it Quote Link to comment
Iwuzere Posted November 20, 2008 Share Posted November 20, 2008 but the 2800ml jug has no lid and evaporates in a few weeks, whereas the Eneloop/Infinium/Hybrio ones stay at 2300ml for months Quote Link to comment
+The Forester Posted November 23, 2008 Share Posted November 23, 2008 A useful trick which I learned from AUV technicians is double charging. When a pair or quad of NiMhs have been charged, take them out of the charger and set them aside. Some hours later put them in the charger again and they will increase their stored charge considerably. Of course this presumes that your charger is the type which stops charging automatically when it detects that the batteries seem to be charged. Forget about buying NiCads. They're horribly fussy things which need to be discharged and charged fully every time and will refuse to accept or deliver a charge if you are not extremely careful. NiMhs are much more user friendly. Quote Link to comment
+Matrix Posted November 23, 2008 Share Posted November 23, 2008 A useful trick which I learned from AUV technicians is double charging. When a pair or quad of NiMhs have been charged, take them out of the charger and set them aside. Some hours later put them in the charger again and they will increase their stored charge considerably. Its called peak charging and a rest of 10 - 20 minutes is usually a good idea . Quote Link to comment
+Eclectic Penguin Posted November 24, 2008 Share Posted November 24, 2008 Is this what you are referring to? Sounds like an excellent idea! Yes, that's the web site. I've got a good mind to roll one up now that you've helped me re-discover it! Quote Link to comment
+Bob Smith Posted November 24, 2008 Share Posted November 24, 2008 Be careful using this discharge circuit. No battery likes to be 'overdischarged ' which is exactly what this circuit will do unless you remove the battery as soon as the watch stops. Quote Link to comment
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