Living off the grid

Mk III Human Power Generator by WindStreamPower 30 minutes of pedaling recharges a laptop battery.

Traveling overland by 4x4 truck for more than 3 years while living “off the grid” is not particularly easy. A life on the road quickly reveals how electricity addicted society has become. On the scale of an average household, powering just a laptop sounds like a modest task but the experience proves differently. Without AC mains it’s quite a challenge – it puts a laptop battery well in the spotlight.

Quite a bit of technology is put in place to recharge laptop batteries. A Solar Power System connected to a Laptop Car Charger or Laptop Power Inverter. Then for emergencies the ordinary noisy generator. All this has given a distinct feel to how much power a laptop battery actually contains and what it takes to recharge it.

To put things a bit in perspective; To recharge an average 53Wh laptop battery roughly takes the energy produced on a 30 minute bicycle ride. (A bit of head-wind on average speed but no mountains and luggage) That’s a distance crossed of about 7 Km or 4.3 Miles. However a 53Wh laptop battery takes at least 1,5 hour to recharge – so that’s 22,5 Km or 14 miles in distance crossed – wasting the energy to recharge 2 laptop batteries in the meanwhile.

In the early stages of the overland journey WIFI internet access has been a significant factor in using a laptop. In most cases it was possible to sit down in a café and work from AC mains – simply because short range WIFI hotspots also need power. Over the past 2 years this has shifted to long range 2G and 3G cellular internet access. Making it possible to be online in remote or odd locations. This development put even more pressure on keeping laptop batteries charged through alternative energy sources.

And with al this the quest to save battery power became a sport, reducing laptop electricity consumption to the bare minimum.
 

Laptop battery industry

The world's $71 billion dollar battery market is becoming a hot-house for innovation. The problem is that batteries haven't evolved that quickly as computer technologies. A battery is limited by the laws of physics, in the end it's just a chemical reaction in a box.

Currently, eyes are focused on Lithium-Ion battery technology. A high energy density technology but suffering from thermal run-away - a few DELL laptops reached the news, going up in flames.  With more and more people getting connect to the Internet while on the move, the call for more capacity / higher energy density only gets louder. With the new potential of Nanowire battery technology, based on Lithium-Ion, laptop batteries in the future might take another quantum leap in capacity.
 

Laptop battery technology

Nowadays the average laptop battery is a sophisticated device. It contains a CPU, flash memory and sometimes a battery gauge to indicate the state of charge without having to turn of a laptop to see it. The process used to charge the battery is a well guarded secret for now. Part of laptop battery technology are measures to prevent tampering with the internals.
 

Inside a DELL 53Wh laptop battery

The technology and know-how required to manage Lithium Ion laptop battery cells has evolved rapidly over the past 10 years. With higher Lithium Ion cell capacities, safety became an important requirement. The average 53Wh laptop battery contains a lot of energy in such a small box. Although energy density isn’t growing as rapidly as it did in the past, it’s very likely laptop battery capacity will increase even more.

The price for a quality laptop battery is high and probably remain so for the future. On average a laptop battery on this overland journey never lasted longer than a year. At best the DELL Latitude D610 ran for 3-4 hours on a single battery.
 

Laptop battery trends

3G cellular internet

From a traveling perspective, the growing popularity of prepaid 3G cellular internet will make the demand for bigger laptop battery capacities even stronger. Being in the position to connect to fast wireless internet in places where there’s no AC mains has suddenly made the laptop battery the weakest link.
 

Reduction of laptop power consumption

Although a break-through causing battery capacity to double is unlikely. For the time being there’s more gain in reducing laptop power consumption. Better laptop hardware and more energy efficient operating systems are key.
 

Standardization of laptop batteries and laptop chargers

Another development is standardization of laptop batteries. Although the trend is still faint, being able to use any laptop battery within a brand is already a huge plus. Not to mention to use the same laptop battery across different brands. DELL already has filed patents describing “a legacy mode” where a laptop is designed for multi-capacity laptop batteries. There is only one downside – for lower capacity laptop batteries, CPU speed must be throttled, since the battery can’t deliver the energy required. Hence the “fast” laptop battery is born.
 

Throthling CPU speed already found it's way in DELL laptops when connecting an AC adapter of unknown origin. This trend came to surface unexpectedly through a failure pattern in the DELL battery charging system. The throttling mechanism will  most likely be used in a trend where standard AC adapters are designed for several laptop models within a brand. Hence the "Fast" AC adapter capable of powering high-speed CPU's.
 

Laptop battery benchmark

Laptop battery benchmarking started somewhere in 2000, called MobileMark. With a bigger demand for more capacity, battery re-use and rather high prices, the call for a realistic and dependable benchmark will only get louder. A simple laptop battery test would be a big help.
 

Laptop battery hacking

Driven by high pricing and it’s “black box” image, tampering with laptop battery internals is a steadily growing phenomena. It’s already known as “battery hacking”. Any suspicion towards the laptop battery industry is partly self-inflicted. Testing or recharging individual Lithium Ion cells in dead laptop batteries has in some cases revealed the cells are not so dead after-all. Also there are (unverified) claims where dead laptop batteries suddenly return from the dead just like that.

Unfortunately there is a dark side to battery hacking where dead laptop batteries are revived by a well protected and secret “factory reset” and sold as new or “refurbished”. Laptop batteries suffering a sudden death way before their expected life-time only contribute to existing suspicion. In any case time will tell – making a young industry grow up real fast.