Making batteries last 10 years

[prState]

Here's a story on a retired engineer in Minnesota. What I'm interested in is how he's making SLAs last up to 10 years. When you think about it, if you can use an SLA set at all for any riding that would be quite a savings over time. (maybe I should just write and ask him)

A connoisseur of batteries and a debunker of the so-called breakthroughs that come around like clockwork every couple of years, Hart makes it his business to parse hype from performance. Whenever he hears about a new battery, the 58-year-old self-employed electrical engineer (he did lab work at Eastman Kodak and Honeywell) writes the company and asks for a prototype to be sent to his home in Sartell, Minnesota. "I'm a cheapskate, and sometimes they'll send me a free one," he jokes. So far, he still prefers lead-acid batteries. Using a life-extending charging system he designed himself, he's converting his third electric car to handle 14 of them; a buoyant pride creeps into his voice as he notes that most of the batteries are 8 to 10 years old. "Just like you don't feed an old dog puppy chow," he says, an old dog himself with the white tufts on the sides of his balding head combed up to resemble Mercury's wings, "you treat old batteries differently."

How to Build a Better Battery

 

[john]

He says that they are 8 to 10 years old, but not that he has used them for that long to power a car.

 

[flecc]

Lead acid batteries sulphate over time, especially when lightly used, and some low level cautious reverse changing can clear that and revive the battery fo a further period of use. It's a very dangerous practice though.

Utlimately most lead acid batteries regularly used just run out of lead plate thickness as the lead is used, the plates buckle and short and the battery is finished. Some lead acid batteries are made for long life heavy traction purposes like those on milk floats and they just have much thicker plates to start with.
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[oldosc]

quite,
i have a motor home circa 1990.have travelled 129000 miles we have used three batterys (at least twice have flattened the engine battery..pretty near death to Pb batts
Tenderness plenty of water, slow charging,and good quality batteries they will last a long long time (Until 1958 the plates in Rolls Royce batterys were hand pasted, and the seperators were thicker. They laster 15 years.(also with old friends amnesia helps )

 

[gary Gadget]

I work for a well known Telecoms’ company and we have in use more lead acid paste batteries than any other company and have since the 50's, which includes any car manufacturers you would like to mention. The cells we use are usually sealed and have a useful life of 6 to 8 years being a compromise between cost, performance and replacement labour costs, we used to use a company called “Gates” who have sadly gone and replaced by a newer cheaper china maker and their cells, we used for 10 to 12 years. Providing you do not abuse the cells (we combine 2 ,6 or 12 volt batteries or “cells” into a single 54.5 volt battery) in higher that 25C temperatures as this causes the gassing and can drastically reduce the batteries capacity and only DOD (Depth of Discharge) to 40% you can easily get 1200 full recharge cycles, 400 recharge cycles better than anything else so far). Yes the comments that plates buckle and cause an internal short in a battery is correct, but this usually happens if the cells are subjected to “low cell voltage” by being discharged below the safe voltage or discharged and left without being recharged for long periods of time or manufacturing defects. All modern Ebikes controllers have a safety cut off voltage to stop this and most chargers now are smart and recharge cells in stages. Look after your Battery and it will give years of service, ride and forget and you will end up having to pedal all that dead weight home on you own. The same goes for the newer technologies, LION batteries are made up of cells and have to have BMI circuits built into the battery to ensure they discharge / charge safely (and don’t explode!! they are a chemical reaction energy source) and the controller should shut off if the voltage drops below 31.5V (for 36V LION battery) But all Telco’s I have dealings with have not moved to the newer technologies as the cost is too high. They are only booming on Ebikes because they are lighter and this helps in reducing weight and increases range, and they have a better discharge curve which allows the battery to release more of the stored energy before dropping below the safe cell voltage. If you only do 5 miles buy a small lead acid battery as they are more cost effective and can be recycled. If you need greater range I think the LION batteries offer better performance than other rechargeable’s which are hard to recycle but you will have to pay the premium which can be 5 times the cost of lead and they have not been around long enough to have accurate reliability and longevity results when used on Ebikes.

 

[flecc]

My references to cell plate buckling referred to liquid electrolyte batteries.

SLA paste batteries behave somewhat differently, and their life depends on a variety of things. Not so long ago it was possible to buy them on the retail marklet formulated in one of two ways, either for high discharge cycling as we use them, or the other type that I believe Gary refers to, low current types maintained by trickle charging for standby applications like burglar alarms. The latter can last for a decade, but those in our use wont.
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[gary Gadget]

Hi Flecc, no I was referring to the former. We use them to power the Telephone Exchange Equipment as well as Broadband etc. and though they are for standby they are subjected to monthly full load tests as well as the main use which is to power the equipment, rectifier's that are AC fed are in circuit and the battery takes over if mains is lost or engines run etc. Usual discharge current is just under 30 Amps per battery and we have 3 per rack and usually 5 or 6 racks an exchange (50 or 60 in some London exchanges), they power the full load for an hour and do this as many times as required with our voltage cut off of 44 volts to save the cells from damaging themselves in deep discharge (rated at 100AH). We also use smaller Panasonic and Yuasa Batteries for LLU equipment and they are changed out every 3 years as part of a "no maintenance contract". I have 2 on my Bike now that are 4 years old and still going good. I put this down to the load management and charging program we use. Also some massive 12volt 400Ah units that I would love to fit but I don't think they make a back wheel strong enough yet....let alone me being able to lift a pair up. Also did I say paste I meant gel, stops leaks and a tendency to slosh and move if used on our Mobile GenSets for starting (we use the same Batteries for both)

So yes useful life can be years and years for Lead Acid but I don't think you can say that about the others!

Gary

 

[flecc]

Thanks for that info Gary, very interesting, and good to see what good management can achieve.

You are so right about the other types, best thought of in months rather than years.

LiFePO4 holds out some hope for better though, with charges going into to the thousands, but I'm not yet clear on whether ageing will kill them anyway, used or not, as it does on all the other lithium rechargeable types.
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[gary Gadget]

True, the sad thing is that to get any decent range with Lead Acid they weigh too much to carry and reduce the range just having to pull them along. I like the LION battery, nice and light but I don't like the cost of a new one or the fact they seem to be scarcer than gold dust, especially the new Wisper 13Ah ones.... Now I wonder what the law is on electric trailers attached to an electric bike, that might be an answer

 

[flecc]

I think the law would just regard them as an add on motor, just like any e-bike kit motor, and some are designed with that in mind. This one from the Dutch Cab Bike company is meant to add power to any bike, trike or velomobile, motor and battery in the bottom half, space for luggage in the top half:

There's a whole thread about powered trailers in The Charging Post here.
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