SkyCaddie SG4 - Battery issues/battery life

I got my SkyCaddie SG4 a little over a year ago and have probably used it for 100 - 125 rounds.

For most of this time, the battery would give me 36 good holes in a day for the rare occasions when I played 36 holes.

The last time for me playing 36 in one day was mid-November and the SkyCaddie performed fine for all 36 holes, two days in a row.

Strangely, yesterday the battery ran out of juice on the 18th hole (I was playing only 18 yesterday) -- I was checking the distance for my 2nd shot to the 18th green and got that message about "low battery" and wasn't even able to get the SkyCaddie to give me the distance to the green. BTW, I just finished "fully" charging the battery and the battery charge indicator doesn't look like it's showing the battery is fully charged; it looks more like 7/8 charged.

I am 99.44% sure I fully charged the battery the night before going to the course and am going to make sure it's completely charged before my round on the 31st and will see how it works then. It's possible that for some reason I didn't have a full charge for my round on the 27th but I won't believe it until/unless the battery is still about half charged after my round on the 31st.

Questions:
1. Does anybody know what the battery life of the SG4 battery is? Is it possible/likely that it's only good for about a year?
2. Any other ideas?

Thanks!

Almost all of today's rechargable batteries are meant to be depleted before recharging.

Were you leaving it charging in-between rounds?

I've found the more I charge my phone/laptop/etc. batteries, the faster they lose their charge.

I don't have an answer geared directly toward your question, as I don't own a SkyCaddie, but I just wanted to give my experience with charging batteries.

More then you would ever want to know about battery types,
memory, charge and temperature affects.

http://batteryuniversity.com/index.htm

that's not true with lithium ions. maybe with nicads years ago.

anyways, here's the link to your solution: https://www.skygolfgps.com/p-113-sg4...e-battery.aspx

I design a

lot of battery powered devices for a living and can probably give some advice from practical experience. LiIon batteries don't like to be fully discharged or over-charged. They have a limited lifetime measured in charge/discharge cycles. The more deeply the cell(s) are discharged the more it eats into the lifetime of the cell. The datasheets for most of the LiIon cells I've read give a typical cell life of 200-250 cycles. This is full discharge/charge cycles but each partial cycle also takes away from cell life at a lower rate. As the cycle count increases the capacity of the battery also decreases a small amount. So by the time you have 100 cycles on a pack you may only see 50-85% capacity of the cell compared to when it was new. So if you typically run your GPS until the battery is depleted and you have 100-125 cycles on the pack then I would expect the pack will only have maybe 60-70% of the capacity that it originally had. You see this with laptop batteries all the time. One thing that will prolong the life of LiIon cells is to keep them fully charged all the time. That way the discharges won't be so deep and will prolong the life of the cell. A properly designed charger will not shorten the life of the cells and will keep the cells "topped up" when plugged in all the time. As an example, I keep my cell phone on the charger anytime I'm not using it. The battery pack is 5 years old and is just now showing signs of losing capacity. It's a Samsung phone and has a very good charging stand -- it charges the cell full and keeps the cells topped up without overcharging. I have no idea what kind of charger the SG4 has so I can't recommend whether leaving on charge all the time is a good idea or not. I would definitely charge the unit every time before I was going to play though. Me, I bought the SG3 somewhat for this very reason. Some devices out there have really crappy chargers and will eat cells and the replacements are expensive. I decided I'd rather stick 2600 mAh NiMH cells in my SG3 that I can charge and replace at will -- they are cheap and I can always carry a spare set (or a set of alkalines) in my golf bag when I play.

Really only true for NiCads. Some NiMH cells benefit from periodically being discharged fully (say once every 3-6 months) depending on the cells and the device using them.

For LiIon or Li Polymer cells this is a good thing.

Your phone probably uses NiCads (continuous charge = BAD) but the laptop almost certainly uses LiIon cells. If continuous charge kills the cells then the charger is a crappy design. (Probably a Dell -- I've replaced more battery packs with Dell laptops than any other

)

An excellent site and accurate battery information. I've referred many of my clients to that very site.

You are correct. The OP may also want to look for replacement packs for the Magellan eXplorist 400. The SG3 and SG4 are based on Magellan eXplorist hardware (eXplorist 300 and 400 respectively). I'm pretty sure the LiIon packs for the Magellen GPS 400 units will work fine in the SG4 and probably be cheaper. SkyCaddie accessories tend to be expensive (not unusual for someone using re-badged hardware).

Added: Yep, it appears the replacement batteries for a Magellan eXplorist 400 will work fine in the SG4. It also appears that they can be had online for about half the cost of the battery pack from SkyCaddie. Here's an example: http://www.infinitybatteries.com/p-2...FQINPAodMkRcWw A search for "Magellan explorist 400 battery" turned up loads of potential sources. Most manufacturers won't tell you the things that prolong the life of cells since they make a LOT of money selling replacement battery packs. It sucks and in my opinion is borderline dishonest.

My sg5 battery is only one year old. It stayed charged for 2 rounds and went dead on the third. So I charged it after every two rounds "what else can you do?". All of a sudden it started going dead by the second round on the 3rd or 4th hole. It sounds like I did not over charge it. So I bought a new one for 10.04 on line. Go to amazon blue grass batteries & electronics. Will try this new one and see how it goes? Don