Battery Care

Ok guys, I'm getting a little confused with the various opinions I can find regarding Battery Care, in relation to how it may or may not affect how long it will hold its charge in the field and also how it may or may not affect the actual life of the battery itself.

Firstly, with regards to my mobile phone (which is a new stock, old clam shell type) I was told to try to run it down as much as possible before putting it on charge, and then try to fully charge it before taking it off the charger. Apparently there's some kind or memory thing going on with the battery whereby it won't run down fully, or fully recharge if proper charging procedure isn't followed.

This has got me thinking about my GPX 5000 battery, and the battery in my sP01 Enhancer.

When I'm out detecting the batteries of both have been fully charged the night before. After I get home I usually clean everything up and put it away, and some time during the following week when I'm not busy I charge them both fully. Then, I put them away until my next field trip where once again the night before I put them both on charge before I go.

Thing is, I read on here recently (can't recall which thread or who wrote it sorry) where someone said that you shouldn't let a battery run down less than 50% while stored.

So which is it?? Should I stick them on the charger as soon as I get home and keep charging every few days (or weeks) between outings? or should I just leave it until I go out next time and charge them then?

I should mention here that I only go away for a day at a time, so I never have the problem of having to charge them each night before going out again.

Appreciate your thoughs.

DS

Deepseeker, the 'memory effect' mainly relates to the old NiCad batteries. they were terrible for it, & had to be fully cycled to minimise it.
Lithium batteries are generally happy with any state of charge, although I've read its recommended that they should be stored fully charged, & put on the charger at nominal intervals (2-3months or so) to maintain them. I believe you should never drain any battery dead flat, but Lithium batteries are apparently affected less than other types. What I have read is that most Lithium batteries with built-in charge controllers don't allow the battery to ever go truly dead flat anyway.

Lithium batteries do have a minimum & maximum recommended voltage.
Most recommend not going under 3v or over 4.2v per cell. For a Minelab battery this would mean between 6v to 8.4v would reasonably be expected to be safe & maintain battery life.

You GPX battery has an internal protection circuit to prevent going outside of this. I think max charge is around ~8.2v.
GPX detectors will also shutdown if your battery reaches 7.1v (3.55v per cell) so it is well above recommended low battery points.

I've seen it recommended that li ion batteries be stored long term at 40% charge (approx. 7v) & funnily enough Minelabs shutdown voltage of 7.1v is just above this.

Minelab said:

"There is no need to fully discharge the Li-ion
battery before recharging, it can be recharged at any time
you are not detecting."

"Other very important contributors to capacity
fade are deep or over-discharge, and leaving a
battery fully discharged for long periods of time before recharging. These conditions should be
avoided wherever possible to minimise capacity
fade and obtain optimum cycle life. Minelab
detectors shut down at a certain minimum
voltage of the battery in order to prevent the battery being deep discharged. Also, the
battery pack itself has an electronic protection
circuit on board to prevent this from happening
in case of a short circuit when the battery is not
connected to the detector. Recharging your
battery shortly after draining it to nearly empty,
and not leaving it empty, will reduce this effect."

Click to expand...

I would say keep doing what you're doing. It's a similar charging routine to what I follow & mine (touch wood) haven't died on me yet.

I charge all my battery equipment as soon as I'm finished for the day, GPX battery, sP01, wireless tx and headphones.
I'll do this daily if out for a few days via my 4x4 and then on my way home leaving them fully charged until next trip.
I'm a firm believer in not leaving batteries under charged overnight so it's just a habit I've gotten into once finished for the day.

Thanks so much guys :Y: It's just that a genuine Minelab battery appears to be a rather costly replacement, so I just want to make sure that I get the maximum reliable use/life out of it. Obviously with such modern inbuilt protection and components that explains the price

Interestingly DJI Mavic Pro have an intelligent Lithium Polymer battery which has an...

Quote: Auto-Discharging Function: To prevent swelling, the battery automatically discharges to below 65% of total power when it is idle for more than ten days. It takes around two days to discharge the battery to 65%. It is normal to feel moderate heat being emitted from the battery during the discharge process. Discharge thresholds can be set in the DJI GO app. ...from DJI Operational Manual.

Presumably this will prolong the life of these batteries.

Hi 19.3,

The Mavic Pro battery actually charges up to about 4.5v/cell as compared to most normal li-ion/li-po cells. I can't remember the exact name for the cell type used in the Mavic battery. So with that in light, that is why they recommend that the battery be stored in a partially discharged state as storing a battery in an overcharged state for long periods can cause damage to the cell.

For the Gpx battery, if it is charged up and stored, that is no problem. As long as it remains above the low voltage cutoff, everything should be fine. Critical low voltage on li-ion/li-po cells is when damage generally happens. After a cell has been over-discharged it will most likely suffer permanent damage and not store as much energy any more.

Cheers Mick

my gpx batteries sit from month to month and have no detrimental effects , lithium has a very very low self discharge rate :Y:

The general rule I use for all types of rechargeable batteries is; (with the exception of those with memory effect - NiCad)

Charge often, charge properly and don't flatten them with use.

After a days use, fully charge the 5000 battery, the 2300 C cells or if you have the Lithium 3.6V mod those as well. If you have a light day of detecting then at the end of the day is fine. If you are out there from the "crack of" to dusk, then put them on charge in the car at lunch time if you can or on the way home.

G'day

Batteries seem to just last as long as they want to,often crapping themselves without any warning, the method I have found that what works for me the best is to cycle the batteries in use, never store them when flat or partly charged, keep them clean and dry when stored, take them out every month or so and charge them up during the off season, by cycling the batteries I mean that I will fully charge both my batteries before a trip and then use one battery for a couple of days and then switch over to the other battery for a couple of days, that way they are both getting charged and discharged.

I have been told that this is a waste of time but I will do it anyway as I reckon it works, my original 4500 battery is now about ten years old and and my spare about maybe 7 years old, both are still being used each season with out any issues, I do the same with my other batteries as well, li-ion ones and all other aa and aaa rechargeables that I use for the radios and gps, and my other detectors, Sdc2300 and also Sovereign gt that I run on li ion batteries as well.

A bit of time and care will save you money in the long run for sure.

cheers

stayyerAU